Linkage localization of TGFB2 and the human homeobox gene HLX1 to chromosome 1q.

We have identified genetic variation within two human genes, transforming growth factor-beta 2 (TGFB2) and the homeobox gene HB24 (HLX1). Reported here are four human RFLPs and SSCPs for TGFB2 in humans and gorillas. In addition, we describe an RFLP and a SSCP for HLX1. We propose that HLX1 is the human homologue of the mouse homeobox gene Hlx based on extensive sequence homology between the genes and the close proximity of both genes to TGFB2 in their respective species. We also report the chromosomal localization of HLX1 to the long arm of human chromosome 1. Finally, utilizing the polymorphisms described for TGFB2 and HLX1, we have been able to localize these genes within a framework map of the distal long arm of chromosome 1 and to study the linkage relationship between these two genes. Pairwise linkage analysis shows that these two genes are linked, with a recombination fraction of 3.1% and a lod score of 14.49.