CENTROMERIC ALPHOID SEQUENCES ARE BREAKAGE PRONE RESULTING IN PERICENTROMERIC INVERSION HETEROMORPHISM OF QH REGION OF CHROMOSOME-1

Structural variations in the pericentromeric region of chromosome 1 ar e considered the norm. We characterized a chromosome 1 with an inversi on by FISH-technique and suggested that the origin of pericentromeric heteromorphisms is far more complex than previously suggested. It is p ostulated that similar to the centromeric alphoid DNA sequences of chr omosome 9, chromosome 1 also possesses a ''breakage prone'' centromeri c domain which maybe a possible cause of such inversions involving the secondary constriction region.