A-2-->G transition at the 3' acceptor splice site of IVS17 characterizes the COL2A1 gene mutation in the original Stickler syndrome kindred.
Hereditary progressive arthro-ophthalmopathy, or "Stickler syndrome," is an autosomal dominant osteochondrodysplasia characterized by a variety of ocular and skeletal anomalies which frequently lead to retinal detachment and precocious osteoarthritis. A variety of mutations in the COL2A1 gene have been identified in "Stickler" families; in most cases studied thus far, the consequence of mutation is the premature generation of a stop codon. We report here the characterization of a COL2A1 gene mutation in the original kindred described by Stickler et al. [1965]. Conformational sensitive gel electrophoresis (CSGE) [Ganguly et al., 1993] was used to screen for mutations in the entire COL2A1 gene in an affected member from the kindred. A prominent heteroduplex species was noted in the polymerase chain reaction (PCR) product from a region of the gene including exons 17 to 20. Direct sequencing of PCR-amplified genomic DNA resulted in the identification of a base substitution at the A-2 position of the 3' splice acceptor site of IVS17. Sequencing of DNA from affected and unaffected family members confirmed that the mutation segregated with the disease phenotype. Reverse transcriptase-PCR analysis of poly A+ RNA demonstrated that the mutant allele utilized a cryptic splice site in exon 18 of the gene, eliminating 16 bp at the start of exon 18. This frameshift eventually results in a premature termination codon. These findings are the first report of a splice site mutation in classical Stickler syndrome and they provide a satisfying historical context in which to view COL2A1 mutations in this dysplasia.
Williams
C J
CJ
Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
Ganguly
A
A
Considine
E
E
McCarron
S
S
Prockop
D J
DJ
Walsh-Vockley
C
C
Michels
V V
VV
D000293:Adolescent; D000368:Aged; D001483:Base Sequence; D002675:Child, Preschool; D018388:Codon, Terminator; D003094:Collagen / Q000235:genetics*; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D005128:Eye Diseases / Q000235:genetics*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007592:Joint Diseases / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009154:Mutation; D009216:Myopia / Q000235:genetics; D010375:Pedigree; D016133:Polymerase Chain Reaction / Q000379:methods; D012326:RNA Splicing; D012333:RNA, Messenger / Q000235:genetics; D012163:Retinal Detachment / Q000235:genetics*; D013577:Syndrome
D018388:Codon, Terminator; D012333:RNA, Messenger; D003094:Collagen