USH1K, a novel locus for type I Usher syndrome, maps to chromosome 10p11.21-q21.1.
We ascertained two large Pakistani consanguineous families (PKDF231 and PKDF608) segregating profound hearing loss, vestibular dysfunction, and retinitis pigmentosa; the defining features of Usher syndrome type 1 (USH1). To date, seven USH1 loci have been reported. Here, we map a novel locus, USH1K, on chromosome 10p11.21-q21.1. In family PKDF231, we performed a genome-wide linkage screen and found a region of homozygosity shared among the affected individuals at chromosome 10p11.21-q21.1. Meiotic recombination events in family PKDF231 define a critical interval of 11.74 cM (20.20 Mb) bounded by markers D10S1780 (63.83 cM) and D10S546 (75.57 cM). Affected individuals of family PKDF608 were also homozygous for chromosome 10p11.21-q21.1-linked STR markers. Of the 85 genes within the linkage interval, PCDH15, GJD4, FZD4, RET and LRRC18 were sequenced in both families, but no potential pathogenic mutation was identified. The USH1K locus overlaps the non-syndromic deafness locus DFNB33 raising the possibility that the two disorders may be caused by allelic mutations.
Division of Pediatric Ophthalmology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
Thomas J
TJ
Jaworek
Rashid
R
Bhatti
Noreen
N
Latief
Shaheen N
SN
Khan
Saima
S
Riazuddin
Zubair M
ZM
Ahmed
D000293:Adolescent; D000328:Adult; D000483:Alleles; D000070585:Cadherin Related Proteins; D015820:Cadherins / Q000235:genetics; D002648:Child; D002874:Chromosome Mapping / Q000379:methods*; D002879:Chromosomes, Human, Pair 10 / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D056426:Genetic Loci; D020022:Genetic Predisposition to Disease; D055106:Genome-Wide Association Study; D006319:Hearing Loss, Sensorineural / Q000235:genetics; D006720:Homozygote; D006801:Humans; D008126:Lod Score; D008297:Male; D008540:Meiosis; D008875:Middle Aged; D010154:Pakistan / Q000208:ethnology; D010375:Pedigree; D011995:Recombination, Genetic; D052245:Usher Syndromes / Q000235:genetics*; D055815:Young Adult
C498835:CDHR15, human; D000070585:Cadherin Related Proteins; D015820:Cadherins