Identification of novel KIT gene mutations in two Chinese families with piebaldism / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To screen for potential mutations of KIT gene for two Chinese families affected with piebaldism in order to facilitate genetic counseling and assisted reproduction.</p><p><b>METHODS</b>Peripheral blood samples were collected from 2 patients of family 1 and the proband and 3 unaffected members of family 2 for the extraction of DNA and RNA. PCR-sequencing and reverse transcription PCR-sequencing were used to screen KIT mutations.</p><p><b>RESULTS</b>All of the patients from family 1 were found to carry heterozygous IVS12+2-+7delinsACATCTTTA, a splicing mutation undocumented in the human gene mutation data base (HGMD) database. This mutation has resulted in c.1765-1779del in cDNA and p.Gly592Ala/del:E12, which has led to skipping of exon 12 and no expression of cDNA. The proband from family 2 has carried a heterozygous c.2401A>C mutation in KIT gene. The same mutation was not found in unaffected members.</p><p><b>CONCLUSION</b>We have attained definite diagnosis for both families, which has facilitated genetic counseling and assisted reproduction for our patients and their family members.</p>

Mutation screening of the F VIII gene in 10 hemophilia A families / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To identify the F VIII gene mutations of patients and suspected female carriers in 10 Hemophilia A (HA) families, and to guide the prenatal diagnosis.</p><p><b>METHODS</b>PCR, denaturinghigh performance liquid chromatogramphy (DHPLC) and DNA sequencing technologies were applied to screen the F VIII gene of 8 HA patients and 12 suspected female carriers in the 10 families. Linkage analysis was performed by using St 14(DXS 52), intron 13 (CA)n and EX18/Bcl I of the F VIII gene in the HA families. In prenatal diagnosis, we screened the same mutation found in the patients. PCR-restriction fragment length polymorphism was applied to detect the new missense mutations of F VIII gene in 100 unrelated healthy individuals to exclude the possibility of polymorphism.</p><p><b>RESULTS</b>Five missense mutations, 3 frameshift mutations, 2 nonsense mutations and 2 single nucleotide polymorphism (SNP) were identified in 10 the HA families. Among them, c.878A to G, c.1015A to G, c.6870G to T, c.1282delA, c.3072_3073insT, c.4880_4881insA and c.5000G to A were novel mutations or polymorphism. No missense mutations c.878A G, c.1015A to G and c.6870G to T, were found in the 100 healthy unrelated controls. (2) Nine suspected female carriers were confirmed at the gene level. (3) X risk chromosome could be determined to in 4 HA families by genetic linkage analysis. (4) Among the four fetuses for prenatal diagnosis, 2 were normal, 1 was carrier and the remaining 1 was a patient.</p><p><b>CONCLUSION</b>Six novel mutations, i.e., c.878A to G, c.1015A to G, c.6870G to T, c.1282delA, c.3072_3073insT and c.4880_4881insA, were identified in this study. PCR, DHPLC and DNA sequencing could be used to screen the gene mutations of HA patients, to carry out carrier detection and prenatal diagnosis of HA families efficiently, by combining with restriction endonuclease analysis and genetic linkage analysis.</p>