Gene mutation analysis of a collodion baby / 中华儿科杂志

<p><b>OBJECTIVE</b>To determine the mutations pattern of the genes of a collodion baby.</p><p><b>METHODS</b>Collodion baby is a genetic heterogeneous disease caused by mutations of several genes. Since the most common mutations were observed in TGM1 gene, this gene was chosen for mutation screening. The screening was carried out by PCR and direct sequencing. The allele specific primers were designed for a missense mutation and allele-specific (AS) PCR was carried out in 50 normal individuals for population study.</p><p><b>RESULTS</b>Three novel alterations were detected in TGM1 gene of the proband, a missense mutation c.463C > T (p.Arg155Trp) in exon 3, a nonsense mutation c.578G > A (p.Trp193X) in exon 4, and a single nucleotide deletion (c.694delG) also in exon 4 of TGM1 gene. This infant's father was heterozygote of c.694delG mutation, while his mother carried the two mutations (c.463C > T and c.578G > A) on the same chromosome. The missense mutation was not detected in his father and in any of the control individuals by AS-PCR.</p><p><b>CONCLUSION</b>Three novel mutations were identified in TGM1 gene in a Chinese collodion baby. A double mutation (c.463C > T and c.578G > A) located on the maternal allele while the c.694delG deletion on the paternal allele.</p>

A Simplified Approach for Detecting Homologous Deletion of SMN1 Genes in Spinal Muacular Atrophy / 医学研究杂志

Objective To develop a rapid,reliable and convenient approach for diagnosing the homozygous deletion of SMN1 gene.Methods SMN1 gene was amplified specifically with double allele-specific PCR(AS-PCR).Meanwhile,one inrelevant gene was amplified as internal control by PAGE and agarose gel electrophoresis analysis to determine whether the sick children were with homozygous deletion of SMN1 genes.Results The homozygous deletion of exon7 in SMN1 gene was identified by agarose gel electrophoresis or PAGE accurately.Conclusion Compared to PCR-RFLP and DHPLC used in the past,this approach can diagnose homozygous deletion of SMA much more accurate,easier and more convenient without completed following analyses.

A Novel Mutation of ADAR Gene Identified in a Chinese Pedigree with Dyschromatosis Symmetrical Hereditaria / 医学研究杂志

Objective To discover the mutation of ADAR gene in a pedigree with dyschromatosis symmetrical hereditaria(DSH). Methods We investigated this family and collected blood samples of the individuals in this family. Mutation screening was carried out by PCR and direct sequencing. The allele specific primer was designed for the mutation point, and allele-specific PCR was carried out on the patients, normal family members and 40 normal individuals. Results A single nucleotide deletion (c.1642 delC) was identified in exon3 of ADAR gene in the patients of this family. This mutation was not detected in the normal family members and in any of the control individuals. Conclusion This single nucleotide deletion was responsible for the disease in the family.