Genetic diagnosis for a Chinese Han family with hereditary multiple osteochondromas / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To identify the genetic cause for a Chinese Han family affected with hereditary multiple osteochondromas.</p><p><b>METHODS</b>Two patients, five unaffected relatives of the family and 100 unrelated healthy controls were collected. The coding sequences and intron/exon boundaries of EXT1 gene were amplified with polymerase chain reaction (PCR) and sequenced.</p><p><b>RESULTS</b>A heterozygous c.600G>A (p.Trp200X) mutation in exon 1 of the EXT1 gene was detected in the patients. The same mutation was not found in unaffected family members and 100 healthy controls.</p><p><b>CONCLUSION</b>The hereditary multiple osteochondromas in the family is caused by a nonsense mutation (p.Trp200X) in the EXT1 gene.</p>

Clinical investigation of a Chinese family with hypotrichosis simplex of the scalp and mutational analysis of CDSN gene / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To analyze clinical symptoms and disease-causing mutations of corneodesmosin (CDSN) gene in a Chinese family affected with hypotrichosis simplex of the scalp and to establish a method for prenatal diagnosis.</p><p><b>METHODS</b>Family survey and clinical examinations were carried out to determine the inheritance pattern. Three patients and 7 unaffected relatives from the family, in addition with 100 unrelated healthy controls were recruited. Genomic DNA from peripheral blood leukocytes was extracted. Five pairs of primers were designed based on the CDSN gene sequence. Exons and flanking regions of the CDSN gene were amplified using polymerase chain reaction (PCR). Potential mutations were analyzed through direct sequencing and comparison by BLAST.</p><p><b>RESULTS</b>The type of alopecia of the family was diagnosed as hypotrichosis simplex of the scalp with an autosomal dominant inheritance pattern. A nonsense mutation (C717G) in cDNA sequence of the CDSN gene was identified in all three patients of the family, which resulted in a premature stop codon (Y239X). The same mutation was not found among healthy members of the family and 100 healthy controls.</p><p><b>CONCLUSION</b>A Chinese family was diagnosed with hypotrichosis simplex of the scalp, which was caused by a novel nonsense mutation (Y239X) in the CDSN gene.</p>

Mutation analysis of FGFR3 gene in a family featuring hereditary dwarfism / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the clinical symptoms and potential mutation in FGFR3 gene for a family featuring hereditary dwarfism in order to attain diagnosis and provide prenatal diagnosis.</p><p><b>METHODS</b>Five patients and two unaffected relatives from the family, in addition with 100 healthy controls, were recruited. Genome DNA was extracted. Exons 10 and 13 of the FGFR3 gene were amplified using polymerase chain reaction (PCR). PCR products were sequenced in both directions.</p><p><b>RESULTS</b>All patients had similar features including short stature, short limbs, lumbar hyperlordosis but normal craniofacial features. A heterozygous mutation G1620T (N540K) was identified in the cDNA from all patients but not in the unaffected relatives and 100 control subjects. A heterozygous G380R mutation was excluded.</p><p><b>CONCLUSION</b>The hereditary dwarfism featured by this family has been caused by hypochondroplasia (HCH) due to a N540K mutation in the FGFR3 gene.</p>