We report here two cases describing extremely rare condition of homozygosity of pericentric inversion of chromosome 9 with trisomy of chromosome 21. One of the cases also carried a Robertsonian translocation involving chromosome 14 and 21. The other case carried homozygosity of pericentric inversion of chromosome 9 with trisomy of chromosome 21. These two cases may provide a valuable evidence to establish the association between pericentric inversion of chromosome 9 and Down syndrome which has been debated in the medical community.
