Localization of the human UBA52 ubiquitin fusion gene to chromosome band 19p13.1-p12.

Because of the conservation of the ubiquitin coding sequence and the number of transcriptionally active genes and reverse-transcribed pseudogenes, it has not been possible to use ubiquitin cDNA clones to map the functional ubiquitin genes. The UBB and UBC polyubiquitin genes have previously been mapped by the use of specific intron or 5' flanking sequence probes. In this study, we have used an intron sequence from the UBA52 gene for chromosome mapping studies. Analysis of somatic cell hybrids containing individual human chromosomes indicated that the UBA52 gene is located on chromosome 19. In situ hybridization studies confirmed the chromosomal localization but showed two peaks of hybridization: a major one over 19p13.1-p12 and a secondary one over 19q12-q13.11. Because the peak of hybridization over 19p13.1-p12 was consistently the strongest in five individuals, it is likely that this is the location of the UBA52 gene. Thus far, three of the four transcriptionally active ubiquitin genes have been assigned to separate chromosomes.