The Human Y Chromosome: Overlapping DNA Clones Spanning the Euchromatic Region

TLDR

The study aims to produce a detailed map of overlapping Y chromosome clones to accelerate future research. The authors constructed a physical map by assembling 196 YAC clones from a male, screening for 160 sequence‑tagged sites, and ordering them into a single overlapping array. The resulting map spans over 98 % of the Y chromosome’s euchromatic region, assigns 207 loci to 127 intervals with ~220‑kb spacing, and shows genes distributed among X‑homologous, Y‑specific repetitive, and single‑copy sequences.

Abstract

The human Y chromosome was physically mapped by assembling 196 recombinant DNA clones, each containing a segment of the chromosome, into a single overlapping array. This array included more than 98 percent of the euchromatic portion of the Y chromosome. First, a library of yeast artificial chromosome (YAC) clones was prepared from the genomic DNA of a human XYYYY male. The library was screened to identify clones containing 160 sequence-tagged sites and the map was then constructed from this information. In all, 207 Y-chromosomal DNA loci were assigned to 127 ordered intervals on the basis of their presence or absence in the YAC's, yielding ordered landmarks at an average spacing of 220 kilobases across the euchromatic region. The map reveals that Y-chromosomal genes are scattered among a patchwork of X-homologous, Y-specific repetitive, and single-copy DNA sequences. This map of overlapping clones and ordered, densely spaced markers should accelerate studies of the chromosome.