ABSTRACT
Objective To determine the pathogenic mutant gene and the classification for 2 Chinese families with congenital fibrosis of the extraocular muscles (CFEOM) by using candidate genes methods.Methyls All members in the 2 Chinese families with CFEOM were collected and underwent for clinical data collection,including medical history,physical examination and 5-8 mL peripheral venous blood for DNA extraction.Exon 2,8,20,21 of KIF21A,exon 1,2,3 of PHOX2A/ARIX,exon 1,2,3,and 4 of TUBB2B and exon 1,2,3,4 of TUBB3 were selected and synthesized by PCR,and the amplified samples were purified for sequences analysis by Chromas2.3 and DNAman7.0 software.Results There were 9 members developed CFEOM in family 1,with the typical CFEOM characteristics.The mutation site was located in KIF21A (exon 21),2860C ＞ T;and 4 patients in family 2 suffered this disease,and the typical CFEOM appearance features was in 3 patients.The mutation site was located in TBUU3 (exon 4),1249 G ＞ A.Conclusion The candidate genes methods can be used to identify the pathogenic genes of pedigrees with inherited diseases effectively.Family 1 belongs to CFEOM 1A type,which is the autosomal dominant inheritance with complete penetrance,and family 2 belongs to CFEOM 3A type,whivh is the autosomal dominant inheritance with incomplete penetrance.