[Study of gene mutation in a Chinese family with X-linked congenital nystagmus].
OBJECTIVE
To study the disease-causing gene for a Chinese family with X-linked congenital idiopathic nystagmus.


METHODS
It was a retrospective study. The phenotype of a Chinese family with congenital nystagmus was identified by investigating the history and the clinical features of each family member. The mode of inheritance in this family was ascertained by the pedigree analysis. Linkage analysis was performed to identify the possible locus harboring the disease-causing gene. Direct DNA sequence analysis was performed to find the mutation responsible for this disease.


RESULTS
The positive LOD score was obtained for 10 microsatellite makers on chromosome Xq25-Xq27, and the maximum LOD score with DXS1211 was 3.91. A 2-bp deletion in exon 8 of FRMD7 was detected after direct DNA sequence analysis, which was cosegregated with all patients in this family.


CONCLUSIONS
Congenital nystagmus is a clinically and genetically heterogeneous ocular movement disease. Mutation of the FRMD7 gene is the cause of congenital nystagmus in this family.
Li
Ning-Dong
ND
Tianjin Eye Hospital, Tianjin 300020, China.
Wang
Li-Ming
LM
Cui
Li-Hong
LH
Chen
Xia
X
Zhu
Li-Na
LN
Guo
Xin
X
Zhao
Kan-Xing
KX
D044466:Asian People / Q000235:genetics; D003598:Cytoskeletal Proteins / Q000235:genetics; D005091:Exons; D005260:Female; D050172:Genes, X-Linked; D008040:Genetic Linkage; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics; D018895:Microsatellite Repeats; D009154:Mutation; D020417:Nystagmus, Congenital / Q000235:genetics*; D010375:Pedigree; D010641:Phenotype; D012189:Retrospective Studies; D017422:Sequence Analysis, DNA
D003598:Cytoskeletal Proteins; D008565:Membrane Proteins