Congenital cataract is caused by reduced transparency of the lens resulting from metabolic disorders during the fetal period. The disease shows great heterogeneity both clinically and genetically. We identified a 4-generation ethnic Han Chinese family affected by autosomal dominant congenital perinuclear cataract. The patients underwent full clinical and ophthalmologic examinations to rule out any concomitant disorders. Blood samples were collected and genomic DNA was extracted. Potential mutations in the candidate gene alpha A crystallin (CRYAA) were screened.
Birth defects are structural and/or functional malformations present at birth that cause physical or mental disability and are important public health problems. Our study was aimed at genetic analysis and prenatal diagnosis of congenital anomalies to understand the cause of certain birth defects. Karyotypes and array-comparative genomic hybridization (aCGH) were performed on a pregnant woman, surrounding amniotic fluid, and her husband. A short-stature panel genetic test was conducted in accordance with the phenotype of the fetus.
We investigated the feasibility of interleukin-2 receptor gamma (IL2Rγ) gene based on gene mutation analysis and prenatal diagnosis of X-linked severe combined immunodeficiency (X-SCID). Blood samples of patients and their parents of X-SCID (family 1) and X-SCID (family 2) were collected. IL2Rγ gene sequences of the 2 families were analyzed using bi-directional direct sequencing by polymerase chain reaction. DNA sequence changes in the IL2Rγ gene exon region and shear zone were also analyzed. We also sequenced the IL2Rγ gene in 100 healthy individuals.
Isolated methylmalonic acidemia (MMA) is a genetically heterogeneous disorder caused mainly by deficiency of methylmalonyl-CoA mutase. In the present study, we analyzed MUT gene mutations in 3 Chinese couples with a birth history of isolated MMA. We also provided prenatal diagnoses for the detected mutation. Exons and exon-intron boundaries of the MUT gene were analyzed by polymerase chain reaction and direct sequencing. Prenatal genetic diagnoses were performed by chorionic villus sampling after the genotypes of parents were determined.
The accuracy of prenatal diagnosis for abnormal chromosome diseases by chromosome microarray technology and karyotyping were compared. A literature search was carried out in the MEDLINE database with the keywords “chromosome” and “karyotype” and “genetic testing” and “prenatal diagnosis” and “oligonucleotide array sequence”. The studies obtained were filtered by using the QUADAS tool, and studies conforming to the quality standard were fully analyzed.
Pelizaeus-Merzbacher disease (PMD) is a rare X-linked recessive disorder characterized by nystagmus, impaired motor development, ataxia, and progressive spasticity. Genetically defective or altered levels of proteolipid protein (PLP1) or gap-junction alpha protein 12 gene have been found to be a common cause. Here we report on two large Han Chinese families affected with this disease. The probands of both families had produced sons featuring cerebral palsy that had never been correctly diagnosed. PMD was suspected after careful analysis of family history and clinical features.
We developed a new application of comparative multiplex dosage analysis (CMDA) for evaluation of the ataxin 2 gene. Expansions of the triplet CAG can cause spinocerebellar ataxia type 2 (SCA2), a neurodegenerative disease with an autosomal-dominant mode of inheritance. Molecular diagnosis of SCA2 is routinely based on the use of conventional PCR to detect the CAG expansion. However, PCR does not amplify an allele with an expansion of many triplets (>80), which is typically found in infantile and juvenile forms of SCA2, thus leading to false negatives.
Quantitative fluorescent polymerase chain reaction (QF-PCR) is an accurate and reliable method for rapid detection of aneuploidy; however, it is not routinely used in China. We aimed to validate QF-PCR as a means for prenatal common aneuploidy screening and to analyze the heterozygosities of short tandem repeat (STR) markers in the Chinese population. The sequences of 19 STR markers in chromosomes 21, 18, 13, X, and Y were designed; three kinds of fluoresceins were used to label the primers, and the QF-PCR detecting conditions were explored and optimized.
The purpose of this study was to detect chromosomal aberrations and azoospermia factor (AZF) microdeletions in male patients with reproductive problems and to summarize related clinical features to provide reliable information for evaluating prenatal and preimplantation diagnoses. A large cohort of 5083 men with various phenotypes of male infertility was analyzed via G-banding karyotyping, and Origin 8.0 was used to analyze the prevalence of abnormalities.
Partial trisomy 13q is an uncommon chromosomal abnormality with variable phenotypic expression. We report prenatal diagnosis of partial trisomy 13q in a fetus with partial agenesis of the cerebellar vermis, partial agenesis of the corpus callosum, hydrops and polyhydramnios. G-banding karyotyping, spectral karyotyping and array comparative genomic hybridization (aCGH) analysis of fetal blood were performed. Cytogenetic analysis of fetal blood displayed 46,XX,add(4)(q28). The parental karyotypes were normal. A girl was delivered at 34 weeks gestation; she died within 2 h.