Further Delineation of the Proximal 16p11.2 Microdeletion Syndrome: Novel Findings Among 22 New Individuals.

The recurrent chromosome 16p11.2 BP4-BP5 microdeletion (MIM #611913) predisposes to a neurodevelopmental disorder with variable associated congenital anomalies and susceptibility to early-onset obesity. We identified 22 new individuals with proximal 16p11.2 deletions through retrospective data analysis at our institution and performed phenotyping through in-depth chart review. Our cohort exhibited a spectrum of neurodevelopmental abnormalities largely consistent with other publications, however they also were found to have a higher rate than expected of congenital anomalies, some of which have not yet been reported in association with 16p11.2 microdeletions to our knowledge. This series contributes to the body of data on this population, which we anticipate will continue to evolve along with increased uptake of genetic testing.

A 10-Year Review on Advancements in Identifying and Treating Intellectual Disability Caused by Genetic Variations.

Intellectual disability (ID) is a prevalent neurodevelopmental disorder characterized by neurodevelopmental defects such as the congenital impairment of intellectual function and restricted adaptive behavior. However, genetic studies have been significantly hindered by the extreme clinical and genetic heterogeneity of the subjects under investigation. With the development of gene sequencing technologies, more genetic variations have been discovered, assisting efforts in ID identification and treatment. In this review, the physiological basis of gene variations in ID is systematically explained, the diagnosis and therapy of ID is comprehensively described, and the potential of genetic therapies and exercise therapy in the rehabilitation of individuals with intellectual disabilities are highlighted, offering new perspectives for treatment approaches.

Refractory hypertension complicated with Turner syndrome: A case report.

Hypertension is commonly classified into essential hypertension and secondary hypertension, although definitive classification can be challenging in some cases. Here, we discussed a patient who admitted for refractory hypertension, exhibiting various clinical manifestations including inadequate estrogen secretion, underdeveloped secondary sexual characteristics, primary amenorrhea, short stature, multiple moles, and somatic abnormalities. The patient was finally diagnosed with Turner syndrome (TS) based on clinical findings and chromosomal analysis. The genetic karyotype identified was 46,X,i(X)(q10).

Fetal Hydrops Associated With 47,XXX: A Case Report and Literature Review.

This report aims to investigate the association between 47,XXX and fetal hydrops by examining a clinical case and performing a comprehensive review of the relevant literature. A 34-year-old Japanese woman, gravida 2, para 1, was diagnosed with fetal hydrops at 27 weeks' gestation. Prenatal testing revealed a 47,XXX karyotype. Interventions included thoracocentesis and a thoracoamniotic shunt. A cesarean delivery was performed at 34 weeks and the female neonate initially had respiratory challenges. After 69 days in the neonatal intensive care unit, the infant was discharged in stable condition, and the 47,XXX karyotype was confirmed. This case may add evidence suggesting an association between 47,XXX and fetal hydrops. Chromosomal abnormalities are causes of fetal hydrops, but its association with 47,XXX remains unclear. Providing comprehensive information on this condition to couples is crucial, and considering the inclusion of fetal hydrops in the list of associated conditions might be advisable.

Infertility, reproductive timing and 'cure' in families affected by Turner Syndrome.

This article discusses the influence of a chromosome condition affecting women's reproductive capacity, Turner Syndrome (TS), on affected women's social timing, examining the strategic decisions that are made within families in relation to reproduction, to navigate these disruptions. Based on photo elicitation interviews with 19 women with TS and 11 mothers of girls with TS in the UK, it presents findings from an under-researched topic, TS and reproductive choices. In a social context where motherhood is not only desirable, but expected (Suppes, 2020), the social imaginary of infertility anticipates a future of unhappiness and rejection, an undesirable condition that should be avoided. Accordingly, mothers of girls with TS often expect that their daughter will want to have children. Infertility diagnosed in childhood has a distinctive impact on reproductive timing, as future options may be anticipated for years. This article uses the concept of 'crip time' (Kafer, 2013) to explore how women with TS and mothers of girls with TS experience temporal misfitting based on a childhood diagnosis of infertility, and manage, resist and re-frame this to minimise stigma. The 'curative imaginary' (Kafer, 2013), a social norm where disabled people are expected to desire a cure for their condition, is used as an analogy for infertility, describing how mothers of girls with TS respond to social pressure to plan for their daughter's reproductive future. These findings may be useful both for families navigating childhood infertility and practitioners who support them. This article demonstrates the cross-disciplinary potential of applying disability studies concepts to the context of infertility and chronic illness, where concepts shed new light on the dimensions of timing and anticipation in this context, improving our understanding of the lived experience of women with TS, and how they view and use reproductive technologies.

Onset and progression of puberty in Klinefelter syndrome.

OBJECTIVE: Klinefelter syndrome (KS) (47,XXY and variants, KS) is the most common sex chromosome disorder in humans. However, little is known about the onset and progression of puberty in patients with KS. In this study, we describe the onset and progression of puberty in a large series of boys with KS in a single tertiary centre. DESIGN AND PATIENTS: Retrospective data (Tanner stages, testicular length, testosterone supplementation, levels of luteinizing hormone [LH] and testosterone) before possible testosterone treatment on 72 KS patients with 47,XXY karyotype were reviewed, and G (n = 59 patients) and P (n = 56 patients) stages were plotted on puberty nomograms. MEASUREMENTS AND RESULTS: One boy had a delayed onset of puberty, as he was at the G1 stage at the age of 13.8 years (-2.2 SDs). No observations of delay were made of boys at Stage G2. The progression of G stages was within normal limits in the majority of patients; only few boys were late at G3 (4.1%; 1 out of 24) and G4 (7.4%; 2 out of 27). Testosterone supplementation was started at the average age of 15.5 years to 35 boys (47%), 2 of whom were over 18 years old. LH level was on average 18.2 IU/L (SD: 6.3 IU/L) and testosterone 9.1 nmol/L (SD: 3.1 nmol/L) when testosterone supplementation was started. CONCLUSIONS: Our results suggest that puberty starts within the normal age limits in boys with KS, and testosterone supplementation is not needed for the initial pubertal progression in the majority of patients.

Oral Rehabilitation with Implant-Retained Overdenture in a Patient with Down Syndrome.

Down syndrome, known as trisomy 21, is the most common chromosomal disorder. The disorder affects mental and systemic development as well as oral structure, including dental anomalies, high susceptibility of periodontal disease, and poor quality of alveolar bone. This report presents a case of dental rehabilitation by means of dental implants of a patient with Down syndrome. Two titanium dental implants were placed in the maxilla, and three titanium dental implants were installed in the mandible. One implant was lost during the osseointegration period. The prosthetic rehabilitation was performed with implant-retained maxillary and mandibular overdentures with the Locator attachment system. After a 2-year follow-up period, the patient was doing well, and all implants were clinically stable with no signs of bone loss or inflammation. The present study emphasizes that implant-retained overdentures with Locator attachment system could be a therapeutic option even for patients with Down syndrome. This therapy prevents crestal bone loss around the implants, improves functional and esthetic outcomes, and provides optimum oral hygiene for patients with mild mental impairment. Careful patient selection and education of patients and caregivers are essential considerations for a successful and safe treatment with dental implants in Down syndrome patients.

Application of chromosome microarray analysis in neonatal birth defects / 中华实用儿科临床杂志

Objective@#To explore the application of chromosomal microarray analysis (CMA) in neonatal birth defects and further determine the frequency of chromosome imbalances in neonates with birth defects.@*Methods@#Retrospective analysis was performed in 121 neonates with specific features, such as distinctive facial features, congenital heart disease, congenital malformation, neonatal decreased responsive, hypotonia, seizures and others at the Department of Neonatology, Guangdong Women and Children Hospital from May 2016 to November 2017.All the cases were analyzed by using chromosomal microarray analysis (CMA).@*Results@#A total of 23 (19.0%) patients were identified with pathogenic CNVs, 3 patients (2.5%) with uncertain clinical significant CNVs.There were 5 patients (4.1%)with chromosome numerical abnormalities, 12 patients (9.9%)with microdeletion/microduplication syndrome, 6 patients (5.0%) with chromosome deletion or duplication.All groups whose incidence was sorted from high to low were facial characters(30.3%), congenital malformation(21.6%), neonatal decreased responsive(9.1%) and other indications(6.7%).@*Conclusions@#CMA is a valuable clinical diagnostic tool that allows precise identification of chromosome imbalances as the cause of birth defects in neonates.CMA can detect many more clinically relevant genomic abnormalities than conventional cytogenetic study and assist the clinician in diagnosis, early neonatal intervention, and genetic counseling.

Recién nacida normal con sospecha prenatal de monosomía del cromosoma X debido a mosaicismo confinado a la placenta / Normal newborn with prenatal suspicion of X chromosome monosomy due to confined placental mosaicism

La reciente introducción de las pruebas prenatales no invasivas (NIPT, por sus siglas en inglés) basadas en el ADN libre ofrece un método más preciso que los métodos tradicionales de detección en el suero materno para identificar aneuploidías fetales. La eficacia de las pruebas NIPT para detectar los síndromes de Down, Edwards y Patau se ha demostrado en ensayos clínicos. Sin embargo, los enfoques de las pruebas NIPT que aprovechan la información sobre el polimorfismo de un solo nucleótido (SNP, por sus siglas en inglés) tienen el potencial de identificar triploidías, síndromes de microdeleción cromosómica y otras variantes genéticas no habituales. Para destacar este enfoque de las pruebas NIPT, se presenta un caso poco frecuente de monosomía del cromosoma X debido a mosaicismo confinado a la placenta, del que había una sospecha prenatal por el resultado de una prueba prenatal no invasiva basada en el polimorfismo de un solo nucleótido. Los resultados de las pruebas invasivas (amniocentesis) mostraron una pequeña proporción de mosaicismo del cromosoma X (45, X[5]/46, XX[95]). Después del nacimiento, el cariotipo de la niña no reveló anomalías (46 XX), lo que confirmó que el mosaicismo se limitaba a la placenta. Estos resultados ponen de manifiesto la necesidad del consentimiento informado de la paciente, y del minucioso asesoramiento anterior y posterior a las pruebas, para garantizar que comprenda las limitaciones y las ventajas de dichas pruebas, y las repercusiones de los resultados.

The recent introduction of cell-free DNA (cfDNA)-based noninvasive prenatal testing (NIPT) offers pregnant women a more accurate method than traditional serum screening methods for detecting fetal aneuploidies. Clinical trials have demonstrated the efficacy of NIPT for Down, Edwards and Patau syndromes. However NIPT approaches that take advantage of single-nucelotide polymorphism (SNP) information potentially allow the identification of triploidy, chromosomal microdeletion syndromes and other unusual genetic variants. To highlight this approach of NIPT we present a rare case of confined placental X chromosome monosomy mosaicism that was prenatally suspected with a single-nucleotide polymorphism-based noninvasive prenatal test. The results of invasive tests (amniocentesis) showed small proportion of X chromosome mosaicism (45, X[5]/46, XX[95]). After birth karyotype of the girl revealed no abnormalities (46 XX), confirming that mosaicism was limited to the placenta. These results highlight the need of patient's informed consent and thorough pretest and postest counseling to ensure that they understand the limitations and advantages of the tests and the implications of the resultss.

Normal newborn with prenatal suspicion of X chromosome monosomy due to confined placental mosaicism. / Recién nacida normal con sospecha prenatal de monosomía del cromosoma X debido a mosaicismo confinado a la placenta.

The recent introduction of cell-free DNA (cfDNA)-based noninvasive prenatal testing (NIPT) offers pregnant women a more accurate method than traditional serum screening methods for detecting fetal aneuploidies. Clinical trials have demonstrated the efficacy of NIPT for Down, Edwards and Patau syndromes. However NIPT approaches that take advantage of single-nucelotide polymorphism (SNP) information potentially allow the identification of triploidy, chromosomal microdeletion syndromes and other unusual genetic variants. To highlight this approach of NIPT we present a rare case of confined placental X chromosome monosomy mosaicism that was prenatally suspected with a single-nucleotide polymorphism-based noninvasive prenatal test. The results of invasive tests (amniocentesis) showed small proportion of X chromosome mosaicism (45, X[5]/46, XX[95]). After birth karyotype of the girl revealed no abnormalities (46 XX), confirming that mosaicism was limited to the placenta. These results highlight the need of patient's informed consent and thorough pretest and postest counseling to ensure that they understand the limitations and advantages of the tests and the implications of the resultss.

La reciente introducción de las pruebas prenatales no invasivas (NIPT, por sus siglas en inglés) basadas en el ADN libre ofrece un método más preciso que los métodos tradicionales de detección en el suero materno para identificar aneuploidías fetales. La eficacia de las pruebas NIPT para detectar los síndromes de Down, Edwards y Patau se ha demostrado en ensayos clínicos. Sin embargo, los enfoques de las pruebas NIPT que aprovechan la información sobre el polimorfismo de un solo nucleótido (SNP, por sus siglas en inglés) tienen el potencial de identificar triploidías, síndromes de microdeleción cromosómica y otras variantes genéticas no habituales. Para destacar este enfoque de las pruebas NIPT, se presenta un caso poco frecuente de monosomía del cromosoma X debido a mosaicismo confinado a la placenta, del que había una sospecha prenatal por el resultado de una prueba prenatal no invasiva basada en el polimorfismo de un solo nucleótido. Los resultados de las pruebas invasivas (amniocentesis) mostraron una pequeña proporción de mosaicismo del cromosoma X (45, X[5]/46, XX[95]). Después del nacimiento, el cariotipo de la niña no reveló anomalías (46 XX), lo que confirmó que el mosaicismo se limitaba a la placenta. Estos resultados ponen de manifiesto la necesidad del consentimiento informado de la paciente, y del minucioso asesoramiento anterior y posterior a las pruebas, para garantizar que comprenda las limitaciones y las ventajas de dichas pruebas, y las repercusiones de los resultados.

Clinical, cytogenetic, and molecular outcomes in a series of 66 patients with Pierre Robin sequence and literature review: 22q11.2 deletion is less common than other chromosomal anomalies.

Pierre Robin sequence (PRS) is an important craniofacial anomaly that can be seen as an isolated finding or manifestation of multiple syndromes. 22q11.2 deletion and Stickler syndrome are cited as the two most common conditions associated with PRS, but their frequencies are debated. We performed a retrospective study of 66 patients with PRS and reviewed their genetic testing, diagnoses, and clinical findings. The case series is complemented by a comprehensive literature review of the nature and frequency of genetic diagnosis in PRS. In our cohort 65% of patients had associated anomalies; of these, a genetic diagnosis was established in 56%. Stickler syndrome was the most common diagnosis, comprising approximately 11% of all cases, followed by Treacher Collins syndrome (9%). The frequency of 22q11.2 deletion was 1.5%. Chromosome arrays, performed for 72% of idiopathic PRS with associated anomalies, revealed two cases of 18q22→qter deletion, a region not previously reported in association with PRS. A review of the cytogenetic anomalies identified in this population supports an association between the 4q33-qter, 17q24.3, 2q33.1, and 11q23 chromosomal loci and PRS. We found a low frequency of 22q11.2 deletion in PRS, suggesting it is less commonly implicated in this malformation. Our data also indicate a higher frequency of cytogenetic anomalies in PRS patients with associated anomalies, and a potential new link with the 18q22→qter locus. The present findings underscore the utility of chromosomal microarrays in cases of PRS with associated anomalies and suggest that delaying testing for apparently isolated cases should be considered.

A Case of 17q22 with Interstitial Deletion

Cases of interstitial deletions of the long arm of chromosome 17 are very rare, with only nine cases ever reported worldwide. We describe a 12-year-old boy with profound developmental delay, microcephaly, facial dysmorphism, contracture of the large joints and bilateral hearing loss. A chromosomal study using a peripheral blood sampled revealed 46,XY,del(17)(q22q23). To our knowledge, he is the first case of interstitial deletion of the long arm of chromosome 17 ever reported in Korea.

A Case of Del 13(q24) Syndrome with Multiple Anomalies / 소아과

It has been estimated that chromosomal aberrations account for 2.3% to 3% of normal pregnancies, and of them, 85% are aborted. Therefore, the survival rate of neonates with chromosomal aberrations is very low. Among them, patients with partial deletion of the long arm of chromosome 13 are very rare. The natural history of deletion of the long arm is dependent on the deleted segment. It has been known that patients with proximal deletions not extending into q32 usually show mild to moderate mental retardation, variable minor anomalies, and growth retardation. Patients with more distal deletions, including at least part of q32, usually have severe mental retardation, growth deficiency, and major malformations including microcephaly and CNS defects, distal limb anomalies, eye defects, and gastrointestinal malformation. We report a case of a 13(q24) deletion male infant who showed intrauterine growth retardation, imperforate anus, CNS anomalies, hydronephrosis, clubfoot, clinodactyly and developmental delay, although his deletion site was proximal to q32.