Mapping of a human rRNA gene in the YAC contig surrounding the SMA candidate gene

Abstract

Using the yeast artificial chromosome (YAC) 116 flanking the autosomal recessive spinal muscular atrophy (SMA) gene region, we have screened a human fetal brain cDNA library and isolated the cDNA clone 14-3/9 with an insert size of 2.5 kb. The cDNA clone could be identified as part of the human rRNA gene coding for 28S rRNA with a total size of 5025 bp. The human 28S rRNA is involved in the organization of the 60S ribosomal subparticle and is arranged in a 13-kb pre-rRNA transcription unit that occurs in tandem repeat clusters. Multiple copies of the rRNA gene have been mapped by pulsed field blot hybridization in the YAC contig between YAC 66 and YAC 116, which encompasses the SMA candidate gene, and additionally in the distally localized YAC 153.

An integrated RH map of porcine chromosome 10

“…The swine BAC FPC map is also not contiguous over the same region . In the human genome, there are between 150 and 300 copies of ribosomal RNA gene per haploid genome, that map to the short arms of acrocentric chromosomes 13, 14, 15, 21, and 22 [ 35 ]. Unfortunately, the copy number of the porcine RNR gene on SSC10 is currently unknown, which limits our ability to specifically define the extent of the NOR.…”