Mutation analysis of pathogenic genes in a Henan family affected with congenital stationary night blindness / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To detect genetic mutations associated with autosomal dominant congenital stationary night blindness (ADCSNB) in a family from Henan province.</p><p><b>METHODS</b>Genomic DNA was extracted from peripheral blood samples of 14 family members. Based on 3 genes reported previously, PCR primers were designed and corresponding exons containing the mutation sites were amplified with PCR. PCR products were purified and directly sequenced.</p><p><b>RESULTS</b>A c.281C>T heterozygous missense mutation was detected in RHO gene in all of the patients. This mutation can cause a change of the protein structure (p.Thr94Ile). The same mutation was not detected in normal individuals from the family and 50 normal controls.</p><p><b>CONCLUSION</b>A c.281C>T mutation in RHO gene is responsible for the onset of ADCSNB in this Chinese family and results in symptoms of night blindness.</p>

The mutation spectrum of phenylalanine hydroxylase gene in patients with phenylketonuria in Henan province / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the characteristics of the phenylalanine hydroxylase (PAH) gene mutations in patients with phenylketonuria (PKU) in Henan province, China, in order for providing basic information for clinical genetic counseling and prenatal diagnosis.</p><p><b>METHODS</b>All the exons and partial flanking introns of the PAH gene were detected by polymerase chain reaction (PCR) and bi-directional sequencing in 34 patients with PKU from Henan province.</p><p><b>RESULTS</b>A total of 23 different disease-causing mutations were identified which corresponded to 92.65% (63/68) of the PAH alleles, including 12 missense mutations, 4 nonsense mutations, 4 splicing junction mutations, and 3 deletion mutations. Among them, A156P and P69_S70delinsP(delCTT) were novel mutations; IVS2+ 5G to C, G332E, IVS10-14C to G and L367 to Wfs were reported in Chinese population for the first time according to the PAH database (www.pahdb.mcgill.ca). Among all the 13 exons, exon 7 harbored the most type of mutations, exon 11 and exon 5 the second. The most common mutations included R243Q (17.65%, 12/68), V399V (11.76%, 8/68), IVS4-1G to A (8.82%, 6/68), R400T(7.35%, 5/68), Y166X(5.88%,4/68) and G247R(5.88%, 4/68). In addition, 9 other gene variations were found in this study.</p><p><b>CONCLUSION</b>The mutation spectrum and frequency of the PAH gene of patients with phenylketonuria in Henan province were slightly different from those from other parts of China.</p>