Prenatal diagnosis of a fetus with mosaic trisomy 2 and uniparental disomy of chromosome 2 / 中华围产医学杂志

This paper presented the prenatal genetic analysis of a case of mosaic trisomy 2 combined with uniparental disomy 2. The pregnant women underwent non-invasive prenatal testing in Zhuhai Center for Maternal and Child Health Care on February 2019, which indicated an increased number of chromosome 2. Subsequently, amniocentesis was performed at 21 +2 weeks for prenatal diagnosis. No abnormalities were detected through the karyotype analysis of amniotic fluid cells. Chromosome microarray analysis of uncultured amniotic fluid cells revealed a duplication of 2.3 copies in chromosome 2 and 64.3 Mb regions of homozygosity in the 2q21.2q33.1 region. The comparison of single nucleotide information on fetus-parent chromosome 2 showed that the regions of homozygosity of the fetal 2q21.2q33.1 was paternal uniparental isodisomy (2), with the rest of chromosome 2 being paternal uniparental heterodisomy (2).Ultrasound results at 27 +6, 31 +6, and 34 +5 weeks of gestation showed continued exacerbation of fetal growth retardation with placental abnormalities and fetal blood flow spectrum abnormalities. Due to threatened preterm delivery at 35 +3 weeks, The pregnant woman chose to give up the fetus and delivered a stillbirth.

Prenatal diagnosis and genetic analysis of a female fetus with 46, XX and positive SRY gene / 中华围产医学杂志

We report a case of a pregnant woman with 46,XX karyotype and positive sex-determining region on the Y chromosome ( SRY) gene and her female fetus. Ultrasound examination at 12 +6 gestational weeks indicated a thickened fetal nuchal translucency, and 46, XX with a positive SRY gene was detected in the fetus through quantitative fluorescent-polymerase chain reaction and amniotic fluid karyotype. However, the ultrasound showed that the gender of the fetus was female, which was inconsistent with the phenotype of male syndrome with 46, XX combining positive SRY gene. The fluorescent in situ hybridization (FISH) revealed that the short arm of the Y chromosome translocated to the long arm of one of the X chromosomes, namely Yp11.3-Xq28. In addition, a copy number variation at Yp11.31p11.2 copy (about 1 MB) was found by chromosomal microarray analysis, which validated the result of FISH and was consistent with the mother. After genetic counseling, the parents chose to continue the pregnancy to full term, and no abnormalities were found in the infant during the follow-up.

Application of various genetic techniques for the diagnosis of Prader-Willi syndrome / 中华医学遗传学杂志

OBJECTIVE@#To discuss the advantages and technical limitations of various molecular genetic techniques in the diagnosis of two infants featuring all-round developmental retardation.@*METHODS@#The two patients were initially screened by using chromosomal microarray analysis (CMA). For patient 1, his parents were also subjected to CMA analysis, and the data was analyzed by using ChAS and UPD-tool software. For patient 2, methylation-specific PCR (MS-PCR) was carried out.@*RESULTS@#Patient 1 was diagnosed with maternal uniparental disomy (UPD) type Prader-Willi syndrome (PWS) by CMA and UPD-tool family analysis. His chromosomes 15 were of maternal UPD with homology/heterology. Patient 2 was diagnosed with deletion type PWS by combined CMA and MS-PCR.@*CONCLUSION@#Correct selection of laboratory methods based on the advantages and limitations of various molecular techniques can help with diagnosis of genomic imprinting disorders and enable better treatment and prognosis through early intervention.

Genetic analysis of a fetus with partial 18p tetraploidy syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To analyze a fetus with abnormal cardiac ultrasound by using various techniques and explore its genotype-phenotype correlation.</p><p><b>METHODS</b>Lymphocytes derived from umbilical cord blood sample were subjected to G-banding analysis. Short tandem repeats quantitative fluorescence PCR (STR-QF-PCR) was used for analysis of fetal DNA as an auxiliary test. Low-coverage whole genome sequencing (WGS) was used to detect chromosomal deletion/duplication which exceeded 100 kb in size.</p><p><b>RESULTS</b>The karyotype of the fetus was 47,XN,+mar. As detected by STR-QF-PCR, the copy number of GATA178F11 locus on chromosome 18 was 4, and the duplicated fragment was derived from the mother. WGS suggested that the fetus to be 46,XN,dup(18p11.21p11.32).seq [GRCh37/hg19](10 001-15 378 887)× 4, with the duplicated fragment spanning approximately 15.38 Mb.</p><p><b>CONCLUSION</b>The cardiac malformation of the fetus may be attributed to the partial duplication of chromosome 18p. Combined cytogenetic and molecular methods can facilitate prenatal detection of genetic abnormalities.</p>

Association of GPER gene polymorphism with social function of children with attention deficit hyperactivity disorder / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assess the association of G protein-coupled estrogen receptor(GPER) gene polymorphism with social function of children with attention deficit hyperactivity disorder (ADHD).</p><p><b>METHODS</b>The social function of 135 children with ADHD were assessed by Weiss Functional Impairment Scale-Parent form (WFIRS-P). The coding region of GPER gene of all patients was subjected to Sanger sequencing. The association of polymorphisms with the social function of the ADHD children was analyzed.</p><p><b>RESULTS</b>In the case group, the social function scores of Learning and School and Risky Activities of boys were significantly higher than those of girls (t=2.704, P=0.008; t=2.289, P=0.027). No significant difference was found in the genotypic frequencies of the c.-9T/C and c.789G/A loci between different genders. But the learning and school scores of those with a TC genotype for the c.-9T to C locus were significantly higher than those with a TT genotype (t= 2.159, P=0.033).</p><p><b>CONCLUSION</b>For children with ADHD, the social function of Learning and School of those with a TC genotype of the GPER gene c.-9T/C locus is more severely damaged compared with those with a TT genotype.</p>

Correlation analysis about folate metabolism-related genes of pregnant women with fetal congenital defects / 中国医师杂志

Objective To investigate the relationship between folate metabolism-related gene polymorphism and fetal congenital defects,and discuss the effect of genetic factors on fetal congenital defects.Methods Retrospective analysis was used to investigate the genotype and gene frequency of 5,1O-methylenetetrahydrofolate reductase (MTHFR) C677T,A1298C gene loci and ethionine synthase reductase (MTRR) A66G gene locus in 132 cases of adverse pregnancy pregnant women (case group) and 150 cases normal pregnant women (control group) at the same period.The statistical differences were analyzed between the levels of their serum folate,vitamin B12 (Vit B12) and homocysteine (HCY).Results In the serum of case group,folate was positively correlated with Vit B12,and was negatively correlated with HCY,only HCY of skeletal system defects(6 cases) was higher (t =3.409,P ＜ 0.05).Comparing genotypes frequency of the MTHFR C677T,A1298C gene loci and MTRR A66G gene locus in case group with control group,the difference above was not statistically significant (P ＞ 0.05).In these three gene loci C/T,A/C and A/G allele frequency with the control group,the difference above was not statistically significant (all P ＞ 0.05).Different genotype combinations of MTHFR C667T and A1298C gene loci in control groups had no statistically different from the control group (P ＞ 0.05),and there was no synergy.Conclusions Maternal folate metabolism-related MTHFR and MTRR genes polymorphisms can affect the metabolic products levels accordingly.However,the correlation between the changes and the genetic mechanism of fetal congenital defects needs more large samples study in depth.

Neonatal Screening for Alpha-thalassemia / 中华围产医学杂志

0.05), but significantly lower than 8.3% in Guangzhou area(P