The human Y chromosome is composed of two different parts: a pseudoautosomal 
region shared with the X chromosome which is responsible for sex chromosome 
pairing and a Y-specific part that encodes the sex determining gene. Previously 
we have shown that the pseudoautosomal gene MIC2 only rarely recombines between 
the sex chromosomes and, based on the elevated recombination rates in the 
pseudoautosomal region, we predicted that this gene would lie close to the 
Y-specific region. In this report we describe a test of this prediction using 
long-range restriction mapping techniques. We conclude that MIC2 is less than 
200 kilobases (kb) away from Y-specific sequences. During these experiments we 
have identified an HTF island in a position consistent with the proposed 
location of the human sex determining gene.