A ONE CENTIMORGAN DELETION UNIT ON CHROMOSOME XQ12 IS COMMONLY LOST IN BORDERLINE AND INVASIVE EPITHELIAL OVARIAN-TUMORS

We have used polymerase chain reaction (PCR) amplification of tandem r epeats to study the pattern of allelic loss on chromosome X11.2-q12 in borderline and invasive epithelial ovarian tumors, Using eight micros atellite markers spanning Xq11.2-q12, 41 borderline and 65 invasive ov arian tumors, together with their corresponding normal tissues, were a nalysed, The highest percentage of loss of heterozygosity (LOH) was ob served at the DXS1194 locus in borderline tumors (four of 16 informati ve cases, 25%) and at the androgen receptor (AR) locus in invasive epi thelial ovarian tumors (18 of 47 informative cases, 38%), X chromosome activation studies performed in cases with LOH at the AR locus showed that the allelic loss at the AR locus is not confined to the inactive allele, A one centimorgan region including the AR locus and flanked b y the primers DXS1161 and PGK1P1 was identified as the smallest common loss region in both borderline and invasive epithelial ovarian tumors .