Genetic analysis of a case with mosaicism complex structural aberration of chromosome 18 / 中华医学遗传学杂志

OBJECTIVE@#To determine the karyotype of a patient with mosaicism complex structural aberration of chromosome 18.@*METHODS@#A male patient with a 2-year history of infertility presented at the Center of Reproductive Medicine of the Third Hospital of Peking University in October 2019 was selected as the study subject. Clinical data of the patient was collected. Peripheral blood sample was taken for chromosomal karyotyping, copy number variation (CNV) analysis and fluorescence in situ hybridization (FISH) assay. Semen sample was taken for single sperm CNV analysis.@*RESULTS@#The patient was found to have a karyotype of mos 47,XY,del(18)(q21q23),+r(18)(q21q23)[84]/46,XY,del(18)(q21q23)[9]/48,XY,del(18)(q21q23),+r(18)(q21q23)×2[6]/47,XY,del(18)(q21q23),+r(18)(q21q23×2)[1].ish 47,XY,del(18)(q21q23),+r(18)(q21q23)[84]/46,XY,del(18)(q21q23)[9]/48,XY,del(18)(q21q23),+r(18)(q21q23)×2[6]/47,XY,del(18)(q21q23),+r(18)(q21q23×2)[1]del(18)(q21q23)(D18Z1+,18p+,18q+,WCP18+),r(18)(q21q23)(WCP18+),r(18)(q21q23×2)(WCP18+). No pathogenic CNV was identified. Sequencing of 20 single sperms showed that 1 sperm was normal, 1 had yielded no result, 9 had harbored del(18q), 7 had harbored dup(18q)×2, and 2 had harbored dup(18q)×3. The dup/del fragments had both spanned approximately 33 Mb.@*CONCLUSION@#It is rare for carriers of complex structural and numerical abnormalities of chromosome 18 to have a normal phenotype. Based on the accurate cytogenetic and molecular analyses and the single sperm CNV analysis, the influence of the aberrant karyotype on the gametogenesis may be evaluated.

Genetic analysis of a Chinese pedigree with 18q21.2-q22.3 duplication and deletion in two offspring respectively resulting from a maternal intrachromosomal insertion / 中华医学遗传学杂志

OBJECTIVE@#To provide prenatal diagnosis, pedigree analysis and genetic counseling for a pregnant woman who had given birth to a child featuring global developmental delay.@*METHODS@#A pregnant woman who underwent prenatal diagnosis at the Affiliated Hospital of Southwest Medical University in August 2021 was selected as the study subject. Peripheral blood samples were collected from the woman, her husband and child, in addition with amniotic fluid sample during mid-pregnancy. Genetic variants were detected by G-banded karyotyping analysis and copy number variation sequencing (CNV-seq). Pathogenicity of the variant was predicted based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). Candidate variant was traced in the pedigree to assess the recurrence risk.@*RESULTS@#The karyotypes of the pregnant woman, her fetus, and affected child were 46,XX,ins(18)(p11.2q21q22), 46,X?,rec(18)dup(18)(q21q22)ins(18)(p11.2q21q22)mat and 46,XY,rec(18)del(18)(q21q22)ins(18)(p11.2q21q22)mat, respectively. Her husband was found to have a normal karyotype. CNV-seq has revealed a 19.73 Mb duplication at 18q21.2-q22.3 in the fetus and a 19.77 Mb deletion at 18q21.2-q22.3 in her child. The duplication and deletion fragments were identical to the insertional fragment in the pregnant woman. Based on the ACMG guidelines, the duplication and deletion fragments were both predicted to be pathogenic.@*CONCLUSION@#The intrachromosomal insertion of 18q21.2-q22.3 carried by the pregnant woman had probably given rise to the 18q21.2-q22.3 duplication and deletion in the two offspring. Above finding has provided a basis for genetic counseling for this pedigree.

Uleritema ofriógenes como entidad asociada al síndrome 18p- en un paciente pediátrico / Ulerythema ophryogenes as an entity associated with 18p- syndrome in a pediatric patient

El uleritema ofriógenes es un trastorno cutáneo benigno y poco frecuente que se presenta habitualmente en la infancia. Se caracteriza por pápulas foliculares eritematosas y queratósicas en el lateral de las cejas, que con el tiempo suelen evolucionar a alopecia cicatricial. Dicha entidad puede aparecer como manifestación clínica aislada o asociada a varios síndromes congénitos (18p-, Cornelia de Lange, Noonan y Rubinstein- Taybi, entre otros). Presentamos el caso de un paciente de 13 años con síndrome 18p- que consultó por lesiones puntiformes rugosas al tacto y pérdida de pelo en ambas cejas (uleritema ofriógenes), así como por hiperqueratosis pilar en brazos. Esta tríada, conocida como síndrome de Zouboulis, ha sido poco descrita en la literatura. Se considera que el reconocimiento del uleritema ofriógenes es de crucial importancia ya que, ante su presencia, debería realizarse una anamnesis y una exploración física exhaustivas en búsqueda de otras alteraciones que pudieran orientar a la existencia de un trastorno genético subyacente.

Ulerythema ophryogenes is a benign and rare skin disorder commonly presenting in childhood. It is characterized by erythematous and keratotic follicular papules located on the side of the eyebrows, and which over time tends to evolve into scarred alopecia. This entity may appear as an isolated clinical manifestation or associated with several congenital syndromes (18p-, Cornelia de Lange, Noonan, Rubinstein-Taybi, among others). We present a 13-year-old male with 18p- syndrome who consults for rough lesions and hair loss in both eyebrows (ulerythema ophryogenes), as well as for hyperkeatosis pilaris in both arms. This triad, known as Zouboulis syndrome, has been rarely reported in the literature. We consider that the recognition of ulerythema ophryogenes is of crucial importance since, in view of its presence, comprehensive anamnesis and physical examination should be performed in search of other alterations that could guide the existence of an underlying genetic disord

Genetic analysis of a rare case of Pitt-Hopkins syndrome due to partial deletion of TCF4 gene / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for a child featuring delayed intellectual development.@*METHODS@#The child and his parents were subjected to conventional G-banding karyotyping and single nucleotide polymorphism array (SNP-array) analysis. Suspected copy number variations (CNVs) were verified in both parents.@*RESULTS@#No karyotypic abnormality was found with the child and his parents. SNP-array results for both parents were normal. The child was found to harbor a de novo 172 kb deletion at 18q21.2 with a physical position of 52 957 042-53 129 237. The deletion only involved one OMIM gene, namely TCF4, resulting in removal of its exons 6 to 8.@*CONCLUSION@#The SNP-array assay has facilitated with the diagnosis of this child. Deletion of 18q21.2 region probably accounts for the Pitt-Hopkins syndrome (PTHS) in this patient.

Investigation of Maternal Effects, Maternal-Fetal Interactions, and Parent-of-Origin Effects (Imprinting) for Candidate Genes Positioned on Chromosome 18q21, in Probands with Schizophrenia and their First-Degree Relatives

OBJECTIVE: A popular design for the investigation of such effects, including effects of parent-of-origin (imprinting), maternal genotype, and maternal-fetal genotype interactions, is to collect deoxyribonucleic acid (DNA) from affected offspring and their mothers and to compare with an appropriate control sample. We investigate the effects of estimation of maternal, imprinting and interaction effects using multimodal modeling using parents and their offspring with schizophrenia in Korean population. METHODS: We have recruited 27 probands (with schizophrenia) with their parents and siblings whenever possible. We analyzed 20 SNPs of 7 neuronal genes in chromosome 18. We used EMIM analysis program for the estimation of maternal, imprinting and interaction effects using multimodal modeling. RESULTS: Of analyzed 20 single nucleotide polymorphisms (SNPs), significant SNP (rs 2276186) was suggested in EMIM analysis for child genetics effects (p=0.0225438044) and child genetic effects allowing for maternal genetic effects (p=0.0209453210) with very stringent multiple comparison Bonferroni correction. CONCLUSION: Our results are the pilot study for epigenetic study in mental disorder and help to understanding and use of EMIM statistical genetics analysis program with many limitations including small pedigree numbers.

A case of de novo 18p deletion syndrome with panhypopituitarism

Deletion on the short arm of chromosome 18 is a rare disorder characterized by intellectual disability, growth retardation, and craniofacial malformations (such as prominent ears, microcephaly, ptosis, and a round face). The phenotypic spectrum is wide, encompassing a range of abnormalities from minor congenital malformations to holoprosencephaly. We present a case of a 2-year-old girl with ptosis, a round face, broad neck with low posterior hairline, short stature, and panhypopituitarism. She underwent ventilation tube insertion for recurrent otitis media with effusion. Brain magnetic resonance imaging showed an ectopic posterior pituitary gland and a shallow, small sella turcica with poor visualization of the pituitary stalk. Cytogenetic and chromosomal microarray analysis revealed a de novo deletion on the short arm of chromosome 18 (arr 18p11.32p11.21[136,227–15,099,116]x1). She has been treated with recombinant human growth hormone (GH) therapy since the age of 6 months after diagnosis of GH deficiency. Her growth rate has improved without any side effects from the GH treatment. This case expands the phenotypic spectrum of 18p deletion syndrome and emphasizes the positive impact of GH therapy on linear growth in this syndrome characterized by growth deficiency. Further studies are required to define the genotype-phenotype correlation according to size and loci of the deletion in 18p deletion syndrome and to predict prognosis.

Genotypic and phenotypic analysis of a patient with de novo partial monosomy 18p and partial trisomy 18q / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic cause for a patient with intellectual disability, short stature and multiple congenital anomalies, and to correlate the result with the clinical phenotype.@*METHODS@#Routine karyotyping analysis was carried out on GTG-banded metaphase chromosomes. Single nucleotide polymorphism (SNP) microarray was used to detect microdeletions or microduplications in the patient. Fluorescence in situ hybridization (FISH) was used to ascertain the origin of aberrant chromosomes.@*RESULTS@#The karyotype of the patient was 46,XY,der(18), while both of his parents had a normal karyotype. SNP array identified a 1.23 Mb deletion at 18p11.32-pter (chr18: 136 227-1 370 501, hg19) and a 33.76 Mb duplication at 18q21.1-qter (chr18: 44 250 359-78 013 728, hg19) in the patient. Above finding was confirmed by dual-color FISH with one color for 18p and another for 18q. The patient presented with some common features of 18p deletion and 18q duplication including intellectual disability and growth retardation, in addition with some features of 18p deletion including pectus excavatum, short stature and growth hormone (GH) deficiency. The patient showed progressive improvement of stature with GH therapy. Comparison of patients with previously reported dup(18q)+del(18p) recombinations suggested that, even for patients with similar breakpoints, their phenotypes have ranged from normal to severe and there were no consistent findings.@*CONCLUSION@#As aberrations involving double chromosomal segments often result in phenotypic variability, it has been difficult to correlate the genotype of our patient with his phenotype.

Molecular cytogenetic diagnosis of a case with ring chromosome 18 syndrome / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for a child with developmental delay and congenital syndactyly.@*METHODS@#G-banding chromosomal karyotyping and chromosomal microarray analysis (CMA) were performed on peripheral blood sample from the child.@*RESULTS@#The child was ascertained as 46, XY, r(18)[52]/45,XY,?18[3]. A 18q21.32-q23 deletion was identified by CMA with a size of 19.85 Mb, which has encompassed 99 genes including CTDP1, TXNL4A, TSHZ1, PIGN, RTTN, TNFRSF11A, KDSR and CYB5A.@*CONCLUSION@#Clinical phenotype of the patient with ring chromosome 18 is associated with the size of the euchromatin loss and involved genes. As a useful complement to conventional karyotyping, CMA has provided an powerful tool for delineating complex chromosomal aberrations.

Síndrome del anillo del cromosoma 18: reporte de un caso y revisión de la literatura / Chromosome 18 ring syndrome: case report and review of the literature

El Síndrome del Anillo del Cromosoma 18 (18 [(r)18]) es un trastorno cromosómico que se incluye dentro de las anomalías estructurales desequilibradas donde dicho cromosoma se encuentra en forma de anillo el cual resulta de la pérdida simultánea de ambos segmentos terminales de los brazos corto y largo con la subsecuente fusión de sus extremos, constituyendo una estructura circular que microscópicamente se asemeja a un anillo, de allí su nomenclatura r (del inglés ring, que significa anillo). Tiene una incidencia de 1/40.000 nacidos vivos y hasta la fecha se han reportado aproximadamente entre 80 a 100 casos a nivel mundial sin embargo sólo existen alrededor de nueve reportes de r(18) en mosaico, aislado o asociado con otras alteraciones cromosómicas. A continuación, se presenta el caso de una paciente pediátrica con Síndrome del Anillo del cromosoma 18 estudiado y diagnosticado en la Unidad de Genética Médica de la Universidad Centroccidental Lisandro Alvarado en Barquisimeto, Venezuela, con la correspondiente revisión de la literatura relacionada con este síndrome(AU)

Chromosome 18 Ring Syndrome (18 [(r) 18]) is a chromosomal disorder that is included among the unbalanced structural anomalies in which chromosome 18 has a ring form which results from the simultaneous loss of both terminal segments of the short and long arms with the subsequent fusion of their ends forming a circular structure that microscopically resembles a ring, hence its nomenclature r (of the English ring, which means ring).18r Syndrome has an incidence of 1/40,000 live births; to date approximately 80-100 cases worldwide have been reported. There are only about nine reports of r(18) in mosaic, isolated or associated with other chromosomal alterations. We present a case of a pediatric patient with Chromosome 18 Ring Syndrome, evaluated and diagnosed in the Unidad de Genética Médica of the Universidad Centroccidental Lisandro Alvarado in Barquisimeto, Venezuela with the corresponding review of the literature(AU)

Localization of gestational age reference table and its application in prenatal screening / 浙江大学学报·医学版

To establish a fetal biparietal diameter (BPD)-gestational age formula based on the data of pregnant women from Xiaoshan District of Hangzhou, and to evaluate its application in prenatal screening.Data of 3500 pregnant women with gestational age between 15 weeks and 19 weeks+6 receiving prenatal screening in Xiaoshan Hospital during May 2014 and May 2015 were collected. BPDs were used to establish a localized BPD-gestational age formula. The localized formula was used to evaluate the prenatal screening risks in 1759 pregnant women with irregular menstrual cycles or uncertain last menstrual period (LMP) in Xiaoshan District, and the results were compared with those calculated using formula in LifeCycle 4.0.With localized formula, the total positive rate of Down syndrome, trisomy 18 syndrome and deformity of neural tube was decreased from 6.96% to 5.85% (<0.05), in which the positive rate of Down syndrome decreased (<0.05), that of deformity of neural tube increased (<0.05), and that of trisomy 18 syndrome remained the same (>0.05). The median MoMs of free-hCG β and α-fetoprotein calculated using localized formula were significantly different from those calculated using the formula in LifeCycle 4.0 (all<0.05), and the former ones were more closer to 1. For women of fetus diagnosed with the above diseases, the positive rate calculated using localized formula was almost the same as that calculated using the formula in LifeCycle 4.0.BPD-gestational age formula should be localized based on the statistical analysis of the local population, which will help to reduce the false positive rate, and make the results more accurate and reliable in prenatal screening.

Genotype and phenotype analysis of a child with partial 18q deletion syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the genotype-phenotype correlation of a child with chromosome 18q deletion syndrome.</p><p><b>METHODS</b>G-banded karyotyping, single nucleotide polymorphism array (SNP array) and fluorescence in situ hybridization (FISH) were performed on the child with abnormal phenotypes. Genotype-phenotype correlation was explored following accurate mapping of the breakpoints on chromosome 18q. SNP array was also performed on the genome DNA derived from peripheral venous blood samples from both parents.</p><p><b>RESULTS</b>Chromosomal analysis revealed that the child has a karyotype of 46, XY, del(18) (q23). SNP array analysis detected a 9.855 Mb deletion (chr18: 68 158 880-78 014 123) at 18q22.2q23. Mapping of the breakpoints suggested that the deletion has overlapped with that of distal chromosome 18q deletion syndrome and encompassed several critical regions for this syndrome. SNP array performed on parental samples suggested that the 18q22.2q23 deletion was de novo in origin. FISH analysis of peripheral blood sample from the child confirmed the presence of 18qter deletion.</p><p><b>CONCLUSION</b>The phenotype of this child may be attributed to the deletion of distal 18q22.2q23, which has encompassed several critical regions for the 18q deletion syndrome.</p>

Two false negative cases in noninvasive prenatal testing for fetal chromosomal aneuploidies / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the limitation of non-invasive prenatal testing (NIPT) technique through analyzing two false negative cases.</p><p><b>METHODS</b>Chromosomal karyotyping analysis was performed on umbilical cord blood sample derived from case 1 at 24 weeks' gestation and peripheral blood sample derived from the neonate of case 2. Placental tissues of case 1 and peripheral blood sample of case 2 were also analyzed by high-throughput sequencing for copy number variations (CNVs).</p><p><b>RESULTS</b>For case 1, analysis of fetal umbilical cord blood sample showed a translocation type of trisomy 21, i.e., 46,XY,der(21;21)(q10;q10),+21. There were no obvious abnormalities detected at or near the center of the fetal surface and matrix surface of the placenta. High-thoroughput sequencing showed Chr13:(33 840 001 - 115 100 000)×3[60%]/46,XY[40%] at the edge of the placenta, Chr13:(34 080 001-115100000)×3[54%]/46,XY[46%] at the edge of placenta matrix surface, and trisomy 21 in the umbilical cord tissue. For case 2, analysis of the neonatal peripheral blood sample showed a karyotype of 46,XY,del(18)(q22), which revealed a microdeletion in chromosome 18. High-throughput sequencing of the maternal peripheral blood sample stored during pregnancy confirmed it to be chr18: (62 910 000 - 78 020 000)×1 with 15.1 Mb deletion in the fetus. The neonate was therefore diagnosed with partial monosomy of chromosome 18.</p><p><b>CONCLUSION</b>False negative results of NIPT are related with the fraction of circulating cell-free fetal DNA in the maternal serum. NIPT has limitations in detecting fetal chromosomal microdeletion and confined placenta mosaicisms. Routine ultrasound scan is necessary for pregnant women with low-risk indicated by NIPT.</p>

Prenatal diagnosis of a tetrasomy 18p case using BACs-on-Beads technology and single nucleotide polymorphism array / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To determine the origin of a supernumerary small marker chromosome found in a fetus using prenatal BACs-on-Beads (BoBs) and single nucleotide polymorphism array (SNP-array) assays.</p><p><b>METHODS</b>The fetal sample was subjected to chromosomal karyotyping and BoBs analysis, and the results were validated with genome-wide scanning using a SNP microarray.</p><p><b>RESULTS</b>The fetus was found to have a 47,XX,+mar karyotype. BoBs analysis indicated that there was an amplification between 18p11.32 and 18p11.21, which was verified by the SNP-array assay as a 18.3 Mb duplication occurring at 18p11.32q11.1.</p><p><b>CONCLUSION</b>The karyotype of the fetus was determined as 47,XX,+der18(18p11.32?18q11.1::18q11.1?18p11.32). The duplication has involved important genes including SMCHD1, LPIN2 and TGIF1, which may result in severe malformations in the fetus.</p>

Presence of t(14; 18) translocation in healthy individuals varies according to ethnic background in the Brazilian population

Several groups have demonstrated that healthy individuals can present the t(14;18) translocation. In this report, the presence of the translocation was examined in healthy blood donors in Brazil, a country considered an ethnic melting pot. The translocation was detected by nested PCR in 227 peripheral blood samples from individuals with different ethnic backgrounds. The t(14;18) translocation was found in 45 of 85 White individuals (52.94%); in 57 of 72 Black individuals (79.17%); and in 68 of 70 individuals (97.14%) of Japanese-descent. In conclusion, the frequency of the t(14;18) translocation in the Brazilian population varies according to the ethnic background.

Síndrome de trisomía 18: reporte de un caso clínico / Trisomy 18 syndrome: a case report

Introducción El síndrome de trisomía 18 (T18) ocurre por la presencia de un cromosoma 18 extra completo en la mayoría de los casos. La prevalencia en recién nacidos oscila entre uno en 6.000 a uno en 8.000. Los afectados tienen una elevada mortalidad, solo el 4% supera el primer año de vida. Son pocos los casos reportados que superan los 5 años. Objetivo El objetivo de este artículo es reportar un caso de T18 de larga sobrevida con características en la cavidad oral no descritas en la literatura, y aportar información a médicos y pediatras sobre la etiología, el fenotipo, la sobrevida y el consejo genético. Reporte de caso Paciente de sexo femenino de 7 años con 2 cariotipos realizados en cultivo de linfocitos que mostraron 47,XX+18 en todas las metafases. Con talla y peso bajos, facies dismórficas, retardo severo del desarrollo psicomotor y cognitivo, imposibilidad para alimentarse, ausencia del lenguaje verbal, sordera neurosensorial, marcha atáxica, hipoplasia cerebelosa; genitales con labios mayores y menores hipoplásicos. En la cavidad oral paladar en forma de cúpula, macroglosia, no se observaron incisivos centrales superiores y primeros molares superiores e inferiores. En las radiografías se encuentran hallazgos de formación de las piezas dentales ausentes en la boca, concluyéndose erupción tardía. Conclusiones En los casos de T18 la mortalidad in útero y neonatal es alta, las características clínicas in útero y en recién nacidos han sido bien descritas. Dado que son pocos los casos que superan los 5 años el fenotipo aún está por establecerse. En la paciente aquí reportada se encontraron hallazgos en la cavidad oral no descritos en la literatura.

Introduction The trisomy 18 syndrome occurs due to the presence of an extra chromosome 18 in most cases. The prevalence in infants is estimated at 1:6000 to 1:8000. Those affected have a high mortality rate, only 4% may survive their first year of life. There are few reported cases exceeding five years of age. Objective The aim of this paper is to report a case of trisomy 18 of long survival with oral cavity features not described in the literature, and to provide information to physicians and paediatricians about aetiology, phenotype, survival and genetic counselling. Case report A 7 year-old female patient with 2 karyotypes performed by lymphocyte culture showing 47XX+18 in all metaphases. She presented with growth deficiency, dysmorphic facies, severe psychomotor retardation and cognitive disability, inability to feed, lack of verbal language, sensorineural hearing loss, ataxia, cerebellar hypoplasia, and genitals with hypoplastic labia majora and minora. In the oral cavity: dome shaped palate, macroglossia, absence of upper central incisors and first upper and lower molars in mouth. X-ray findings showed formation of missing teeth, with late eruption being concluded. Conclusions In cases of trisomy 18 syndrome there is an increased risk of neonatal and infant mortality. The clinical characteristics in utero and in neonates have been well described. Since few cases exceeding five years of age have been reported, the phenotype is yet to be established. In the case being reported we describe oral cavity findings not documented in the literature.

Intrauterine death in singleton pregnancies with trisomy 21, 18, 13 and monosomy X / Óbito fetal em gestações únicas com diagnóstico de trissomias dos cromossomos 21, 18, 13 e monossomia do X

Summary A retrospective study from November 2004 to May 2012, conducted at the Obstetric Clinic of Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo (HC-FMUSP), which included 92 singleton pregnancies with prenatal diagnosis of trisomy of chromosome 21 (T21), 18, 13 (T13/18) and monosomy X (45X), with diagnosis performed until the 26th week of pregnancy. The aim of the study was to describe the frequency and to investigate predictors of spontaneous fetal death (FD). Diagnosis (T21, n=36; T13/18, n=25; 45X, n=31) was made at a mean gestational age of 18.3±3.7 weeks, through chorionic villus biopsy (n=22,24%), amniocentesis (n=66, 72%) and cordocentesis (n=4, 4%). Major malformations were present in 45 (49%); with hydrops in 32 (35%) fetuses, more frequently in 45X [n=24/31, 77% vs. T21 (n=6/36, 17%) and T13/18 (n=2/25, 8%), p<0.001]. Specialized fetal echocardiography was performed in 60% (55/92). Of these, 60% (33/55) showed changes in heart morphology and/or function. Fetuses with T13/18 had a higher incidence of cardiac anomalies [60 vs. 25% (T21) and 29% (45X), p= 0.01]. FD occurred in 55 (60%) gestations, being more frequent in 45X [n=26/31, 84% vs. T21 (n=13/36, 36%) and T13/18 (n=16/25, 64%), p<0.01]. Stepwise analysis showed a correlation between hydrops and death in fetuses with T21 (LR= 4.29; 95CI=1.9-8.0, p<0.0001). In fetuses with 45X, the presence of echocardiographic abnormalities was associated with lower risk of FD (LR= 0.56; 95CI=0.27- 0.85, p=0.005). No predictive factors were identified in the T13/18 group. Intra- uterine lethality of aneuploid fetuses is high. Occurrence of hydrops increases risk of FD in pregnancies with T21. In pregnancies with 45X, the occurrence of echocardiographic changes reduces this risk.

Resumo Estudo retrospectivo, de novembro de 2004 a maio de 2012, na Clínica Obstétrica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, incluindo 92 gestações únicas com diagnóstico pré-natal de trissomia dos cromossomos 21 (T21), 18, 13 (T13/18) e monossomia do X (45X), realizado até a 26a semana, com o objetivo de descrever a frequência e investigar preditores do óbito fetal espontâneo (OF). O diagnóstico (T21: n=36; T13/T18: n=25; 45X: n=31) foi realizado em idade gestacional média de 18,3±3,7 semanas, por biópsia de vilo corial (n=22; 24%), amniocentese (n=66; 72%) e cordocentese (n=4; 4%). Malformação major presente em 45 (49%) fetos e hidropisia em 32 (35%), mais frequente no grupo 45X [n=24/31, 77% vs. T21 (n=6/36, 17%) e T13/18 (n=2/25, 8%); p<0,001]. Ecocardiografia fetal especializada foi realizada em 60% (55/92). Destes, 60% (33/55) tinham alterações na morfologia e/ou na função cardíaca. Fetos com T13/18 apresentaram incidência maior de anomalias cardíacas [60 vs. 25% (T21) e 29% (45X); p=0,01]. Ocorrência de OF em 55 (60%) gestações e mais frequente no grupo 45X [n=26/31, 84% vs. T21 (n=13/36, 36%) e T13/18 (n=16/25, 64%); p<0,01]. Análise stepwise demonstrou associação entre hidropisia e óbito em fetos com T21 (LR=4,29; IC95%=1,9-8,0; p<0,0001). Em fetos com 45X, a presença de alterações ecocardiográficas esteve associada com menor risco de OF (LR=0,56; IC95%=0,27-0,85; p=0,005). Não foram identificados fatores preditores no grupo T13/18. A letalidade intrauterina de fetos aneuploides é elevada. A presença de hidropisia aumenta o risco de OF em gestações com T21. Em gestações com 45X, a ocorrência de alterações ecocardiográficas reduz esse risco.

Lack of Association between rs4331426 Polymorphism in the Chr18q11.2 Locus and Pulmonary Tuberculosis in an Iranian Population / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>The effect of rs4331426 polymorphism in the Chr18q11.2 locus on pulmonary tuberculosis (PTB) risk was evaluated.</p><p><b>METHODS</b>This case-control study included 208 PTB patients and 204 healthy subjects. Genotyping of the rs4331426 variant was conducted using polymerase chain reaction restriction fragment length polymorphism.</p><p><b>RESULTS</b>The frequencies of genotypes AA, AG, and GG polymorphisms were 83.1%, 15.9%, and 1.0% in the PTB group and 84.3%, 15.2%, and 0.5% in the control group, respectively. The frequency of the minor (G) allele was 8.9% in the PTB group and 8.1% in controls. Neither genotype nor allele frequencies of the rs4331426 variant showed statistically significant differences between PTB and controls. In addition, stratification by sex showed no significant association between the rs4331426 variant and PTB risk in males or females.</p><p><b>CONCLUSION</b>In conclusion, the results of this study do not support an association between the rs4331426 polymorphism and risk of PTB in an Iranian population.</p>

Genetic and prenatal diagnosis of a pregnant women with mental retardation / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To conduct genetic testing and prenatal diagnosis for a pregnant women with growth retardation, severe mental retardation, and a history of adverse pregnancies.</p><p><b>METHODS</b>G-banded chromosome analysis, fluorescence in situ hybridization (FISH), and whole genome DNA microarray were used to analyze the patient and her fetus.</p><p><b>RESULTS</b>The women was found to be a chimera containing two cell lines with 47 and 46 chromosomes, respectively. Both have involved deletion of 18q21.2q23. FISH analysis suggested that the cell line containing 47 chromosomes has harbored a chromosome marker derived from chromosome 15. The marker has contained chromosome 15p involving the SNRPN locus and part of 15q, which gave rise to a karyotype of 47,XX,del18q21.3,+ish mar D15Z1+ SNRPN+[82]/46,XX,del18q21.3[18]. Whole genome DNA microarray confirmed that a 3.044 Mb fragment from 15q11.2q12 was duplicated, which involved NIPA1, SNRPN and other 17 OMIM genes. Duplication of this region has been characterized by low mental retardation, autism, developmental delay. Meanwhile, there was a 17.992 Mb deletion at 18q21.33q23, which contained 39 OMIM genes including TNFRSF11A and PHLPP1. This fragment was characterized by mental retardation, developmental delay, short stature, and cleft palate. Whole genome microarray analysis confirmed that there was a 17.9 Mb deletion at 18q21.33q23, which has been implemented with mental retardation, general growth retardation, short stature, and cleft palate. After genetic counseling, the family decided to terminate the pregnancy at 21st week.</p><p><b>CONCLUSION</b>Combined chromosome karyotyping, FISH, and whole genome DNA microarray can determine the origin of marker chromosomes and facilitate delineation of its correlation with the clinical phenotype.</p>

Chromosome microarray analysis of patients with 18q deletion syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To analyze the correlation between the genotype and phenotype of 18q deletion syndrome with chromosome microarray analysis (CMA).</p><p><b>METHODS</b>Eight cases with 18q deletion syndrome were selected, including two affected fetuses and six children patients. DNA was extracted and hybridized with Affymetrix CytoScan TM 750K arrays following the manufacturer's standard protocol. The data was analyzed with a special software package.</p><p><b>RESULTS</b>CMA analysis identified pathogenic copy number variations (CNVs) on 18q in all cases, which ranged from 6.612 Mb to 22.973 Mb. NFATC1, GALR1, MBP, SALL3 and TSHZ1 are likely to be causative genes for congenital heart disease, psychological, growth retardation, and cleft palate.</p><p><b>CONCLUSION</b>CMA can precisely locate the breakpoints of 18q and facilitate definition of the genotype-phenotype correlations, which is useful for prognosis.</p>

Prevalência das malformações congênitas identificadas em fetos com trissomia dos cromossomos 13, 18 e 21 / Prevalence of congenital abnormalities identified in fetuses with 13, 18 and 21 chromosomal trisomy

OBJETIVO: Descrever a prevalência das malformações encontradas nos fetos com trissomia dos cromossomos 13, 18 e 21, identificando as mais frequentes em cada condição. MÉTODOS: Estudo transversal retrospectivo, com análise dos casos de trissomias dos cromossomos 13, 18 e 21 que foram diagnosticados pelo cariótipo fetal obtido por amniocentese/cordocentese, entre outubro de 1994 e maio de 2014, em um Hospital de Ensino da região Sul do Brasil. Foram descritas as malformações identificadas no exame ultrassonográfico morfológico e, posteriormente, confirmadas em exames do recém-nascido e/ou por necropsia fetal. Os resultados foram analisados por meio do teste de Fisher e da análise de variância (ANOVA). O nível de significância empregado foi 5% (p=0,05). RESULTADOS: Em 840 exames realizados, foram diagnosticados 69 casos de trissomias; nove deles foram excluídos por desfecho ocorrido fora do Hospital de Clínicas de Porto Alegre ou prontuário incompleto, restando 60 casos (nove de trissomia do cromossomo 13, 26 do cromossomo 18 e 25 do cromossomo 21). As cardiopatias ocorreram, na maioria dos casos, nos três grupos; a comunicação interventricular foi mais prevalente, em 66,7% do grupo da trissomia 13. As anomalias gastrintestinais aconteceram mais no grupo da trissomia 18, principalmente a onfalocele (38,5%; p<0,01). As anomalias geniturinárias foram significativamente mais frequentes no grupo da trissomia 13 (pielectasia com 55,6% - p<0,01; genitália ambígua com 33,3% - p=0,01). Defeitos do sistema nervoso central foram identificados em todos os casos de trissomia 13. Fendas faciais foram mais prevalentes dentre os fetos com trissomia 13 (66,7%; p<0,01). Malformações nas mãos e nos pés tiveram diferenças estatísticas entre os grupos de trissomia. Os defeitos nas mãos ocorreram em 50% dos casos de trissomia 18 e em 44,4% dos casos de 13 (p<0,01); pé torto congênito foi mais comum no grupo da trissomia 18, descrito em 46,2% dos ...

PURPOSE: To describe the prevalence of malformations found in fetuses with trisomy of chromosomes 13, 18 and 21 by identifying the most frequent within each condition. METHODS: A retrospective cross-sectional study with the analysis of trisomy cases of chromosomes 13, 18 and 21 diagnosed through fetal karyotype obtained by amniocentesis/cordocentesis, between October 1994 and May 2014, at a Teaching Hospital in Brazil Southern Region. Malformations identified through morphological ultrasonography were described and, subsequently, confirmed in newborn examinations and/or fetal autopsy. The results were analyzed using Fisher's test and analysis of variance (ANOVA), with a 5% level of significance (p=0.05). RESULTS: Sixty-nine cases of trisomy were diagnosed among 840 exams; nine were excluded due to outcome outside Hospital de Clínicas de Porto Alegre or incomplete records, remaining 60 cases (nine cases of chromosome 13 trisomy, 26 of chromosome 18, and 25 of chromosome 21). In all three groups, heart disease occurred in most cases; the ventricular septal defect was more prevalent and occurred in 66.7% of the trisomy 13 group. Gastrointestinal abnormalities were more prevalent in the trisomy 18 group, especially omphalocele (38.5%; p<0.01). Genitourinary anomalies were more significantly frequent in the trisomy 13 group (pyelectasis, 55.6% - p<0.01; ambiguous genitalia, 33.3% - p=0.01). Central nervous system defects were identified in all cases of trisomy 13. Facial cracks were significantly more prevalent among fetuses with trisomy 13 (66.7%; p<0.01). Hand and feet malformations significantly differed among the trisomy groups. Hand defects occurred in 50% of trisomy 18 cases, and in 44.4% of all trisomy 13 cases (p<0.01); congenital clubfoot was more common in the trisomy 18 group, being detected in 46.2% of fetuses (p<0.01). The abnormalities were found in 50.9, 27.3 and 21.7% of trisomy 18, 13 and 21 cases respectively. ...