title: Characterization of the COL2A1 VNTR polymorphism.
abstract: The variable number of tandem repeat (VNTR) region 3' to the collagen type II gene (COL2A1) was amplified in vitro by the polymerase chain reaction. Subsequent high-resolution gel electrophoresis showed that the five earlier reported alleles could be further subtyped. A total of 17 allelic variants with a heterozygosity of 73.0% were found in 202 unrelated Norwegians. DNA sequencing of 19 COL2A1 alleles has been performed. The internal organization of the VNTR was common for all alleles, as previously shown for a few alleles. Moreover, the polymorphism in the COL2A1 locus is mainly due to variation in the numbers of copies of two repeat units, containing 34 and 31 bp, respectively, and/or to small deletions in either of the two units. DNA sequencing of alleles with the same electrophoretic size revealed no heterogeneity such as an alternating order of the different units, a feature that might have been expected to be the result of unequal crossing-over events. The observed ordered structure of the VNTR and the possibility of single-stranded DNA from the cores in the VNTR forming hairpins and loops suggest that the COL2A1 polymorphism may have evolved mainly by replication slippage mechanisms.
authors.affiliation: Institute of Forensic Medicine, University of Oslo, Rikshospitalet, Norway.
authors.forename: E S
authors.initials: ES
authors.lastname: Berg
authors.forename: B
authors.initials: B
authors.lastname: Olaisen
mesh_terms: D000328:Adult; D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D002648:Child; D003094:Collagen / Q000235:genetics*; D004276:DNA, Satellite / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D005602:France; D006801:Humans; D008969:Molecular Sequence Data; D009664:Norway; D009691:Nucleic Acid Denaturation; D010641:Phenotype; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012091:Repetitive Sequences, Nucleic Acid; D009626:Terminology as Topic
chemical_list: D004276:DNA, Satellite; D003094:Collagen