The cell adhesion regulator (CAR) gene, TaqI and insertion/deletion polymorphisms, and regional assignment to the peritelomeric region of 16q by linkage analysis.

We have identified two types of polymorphism at the CAR (cell adhesion regulator) locus. One is a conventional TaqI polymorphism and the other is an insertion/deletion polymorphism in the coding region. One has the nucleotide sequence AGTGAGGCA (Ser-Gln-Ala) at nt 271-279, whereas the variant has ACAC-AGTGAGGCCCA (Thr-Gln-Ser-Gly-Pro). Although it is not clear whether this variation of amino acids affects the biological function of the gene product, this variant was detected in nine chromosomes among 30 unrelated Japanese individuals. Genetic linkage analysis based on the genotypes of TaqI polymorphism in CEPH families revealed close linkage of CAR to D16S7 and D16S154, which are located in the peritelomeric region of the long arm of chromosome 16.