OBJECTIVE: Screening KIF21A gene mutation in 9 families with congenital fibrosis of extraocular muscles and 7 sporadic cases. METHODS: Families were ascertained and patients underwent complete ophthalmological examinations. The probands of 9 families with CFEOM and 7 sporadic patients were recruited for this study after informed consent. Genomic DNA was isolated from 5 ml peripheral blood samples according to the standard methods. Direct sequencing was performed after PCR amplification to genomic DNA for detection of KIF21A gene mutation. RESULTS: We identified heterozygous KIF21A mutations in 14 of sixteen patients. Twelve of them harbor the most common mutation, c.2860C > T (p.R954W) and two of them harbor the second most common mutation, c2861G > A(p.R954Q). The R954 mutations account for 87.5% (14/16), in which 75% (12/16) are R954W, 12.5% (2/16) are R954Q. CONCLUSION: The R954 mutations are also hotspots in Chinese patients with CFEOM.
OBJECTIVE: Screening KIF21A gene mutation in 9 families with congenital fibrosis of extraocular muscles and 7 sporadic cases. METHODS: Families were ascertained and patients underwent complete ophthalmological examinations. The probands of 9 families with CFEOM and 7 sporadic patients were recruited for this study after informed consent. Genomic DNA was isolated from 5 ml peripheral blood samples according to the standard methods. Direct sequencing was performed after PCR amplification to genomic DNA for detection of KIF21A gene mutation. RESULTS: We identified heterozygous KIF21A mutations in 14 of sixteen patients. Twelve of them harbor the most common mutation, c.2860C > T (p.R954W) and two of them harbor the second most common mutation, c2861G > A(p.R954Q). The R954 mutations account for 87.5% (14/16), in which 75% (12/16) are R954W, 12.5% (2/16) are R954Q. CONCLUSION: The R954 mutations are also hotspots in Chinese patients with CFEOM.