Value of oral mucosa cast-off cells as samples in fluorescent in situ hybridization for the diagnosis of Down's syndrome / 中国当代儿科杂志

<p><b>OBJECTIVE</b>At present, blood and skin biopsy tissues are used in the fluorescent in situ hybridization (FISH) test for the diagnosis of Down's syndrome, however, the samples are usually obtained invasively. This study explores the value of oral mucosa cast-off cells in the FISH test, as samples obtained non-invasively, for the diagnosis of this disorder.</p><p><b>METHODS</b>Peripheral blood and oral mucosa cast-off cells were sampled for the FISH test in 16 children with suspected Down's syndrome between March 2010 and March 2011. Chromosomal karyotype analysis of peripheral blood lymphocytes ("gold standard" for the diagnosis of Down's syndrome) was also conducted.</p><p><b>RESULTS</b>The FISH test, in which both peripheral blood and oral mucosa cast-off cells were examined, showed that 14 children had 21-trosomy syndrome and the other 2 children had normal numbers of cromosome 21. The results of the FISH test were the same as the results of the chromosomal karyotype analysis.</p><p><b>CONCLUSIONS</b>Use of the FISH method to test samples of oral musoca cast-off cells is non-invasive and reliable for the diagnosis of Down's syndrome in children, and is hence worthy of recommendation.</p>

Mutation analysis of KIF21A gene in a Chinese family with congenital fibrosis of the extraocular muscles type I / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To determine the mutation responsible for the congenital fibrosis of the extraocular muscles type I(CFEOM1) in a Chinese family.</p><p><b>METHODS</b>Direct sequencing of exons 20 and 21 in the KIF21A gene was performed for the proband. The mutation c.2860C to T in exon 21 was examined by allele specific-PCR (AS-PCR) analysis in other family members. Haplotype analysis was performed using four STR markers (D12S1668, D12S2194, D12S331 and D12S1048).</p><p><b>RESULTS</b>A heterozygous mutation c.2860C to T in the KIF21A gene was identified in all three affected members with CFEOM1. Haplotype analysis suggested that the mutation might derive from maternal germline mosaicism.</p><p><b>CONCLUSION</b>This Chinese family with CFEOM1 may be caused by a c.2860C to T mutation in the KIF21A gene.</p>

Mutation analysis of the PAH gene in patients with phenylketonuria in Gansu province / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To characterize the mutations of the phenylalanine hydroxylase (PAH) gene in patients with phenylketonuria in Gansu province.</p><p><b>METHODS</b>Mutations of the PAH gene were detected in exons 3, 5, 6, 7, 11 and 12 with flaking introns of PAH gene by PCR and DNA sequencing.</p><p><b>RESULTS</b>Mutations were identified in 45/58 alleles (detection rate: 96.4%), in total of 18 variants. Among them IVS12+5G>C was a novel mutation. The most frequent mutations were R243Q (22.7%), V399V (12.1%), EX6-96A>G (5.2%), R413P (5.2%) and IVS4-1G>A (5.2%), followed by Y356X (3.4%), R111X (3.4%) and INS7+2T>A (3.4%).</p><p><b>CONCLUSION</b>The mutations of the phenylalanine hydroxylase gene in patients with phenylketonuria in Gansu province were similar to that in other areas of China, with obvious difference in mutation rate of some mutations.</p>