A cosmid clone for the 5HT1A receptor (HTR1A) reveals a TaqI RFLP that shows tight linkage to dna loci D5S6, D5S39, and D5S76.
A human neuroreceptor clone (G21), which was isolated by cross-hybridization with the human clone for the beta 2-adrenergic receptor, has recently been shown to encode the gene for the 5HT1A receptor (HTR1A) subtype. In situ hybridization to human metaphase chromosomes mapped the G21 sequence to chromosome 5 at bands 5q11.2-q13. The clone G21 recognizes a SacI RFLP with low heterozygosity (0.13). To increase the informativeness of the HTR1A locus we have isolated two new cosmid clones containing the receptor gene. No polymorphic microsatellites were present in the cosmids. However, one cosmid revealed a new TaqI RFLP that showed tight linkage to new highly polymorphic microsatellites for the loci D5S76, D5S39, and D5S6 in seven British and Icelandic reference pedigrees (maximum LOD of 13.2 with D5S76).