Considering the fact that the PPARD gene is located in the human leukocyte antigen (HLA) complex on chromosomal region 6p, which is frequently affected by deletions and rearrangements in human cancers [37], [38], our observation may suggest loss of heterozygosity in the PPARD loci in tumor cell subclones during tumor development. The gene discussed is PPARD; the disease is neoplasm.