Definition for Pseudoautosomal region
From Biology Forums Dictionary
1) The pseudoautosomal regions, PAR1, PAR2, and PAR3 are homologous sequences of nucleotides on the X and Y chromosomes.
2) The pseudoautosomal region (PAR) is a short region of homology between the mammalian X and Y chromosomes, which has undergone rapid evolution. A crossover in the PAR is essential for the proper disjunction of X and Y chromosomes in male meiosis, and PAR deletion results in male sterility.