RESUMO
<p><b>OBJECTIVE</b>To investigate if hereditary mixed polyposis syndrome (HMPS) locus of two Singapore Chinese HMPS families is identical with the Ashkenazi families.</p><p><b>METHODS</b>Genomic DNA was extracted, multiplex polymerase chain reaction (PCR) was used to amplify 4 microsatellite markers D15S1010, D15S1007, ACTC and D15S118 in 31 individuals from two families. The HMPS locus cosecretion of the markers on 15q13 over a region of 2.8 cM was confirmed by Haplotype and linkage analysis.</p><p><b>RESULTS</b>The disease of haplotype identified in one pedigree was not co-segregated with an affected individual while no definitive disease haplotype could be assigned for the second pedigree. The maximum two-point and multi-point LOD scores at ACTC for the two Chinese families are 0.20 (theta = 0.3) and -5.0 respectively.</p><p><b>CONCLUSIONS</b>Haplotype and linkage analysis indicate that the Ashkenazi haplotypes is not associated with HMPS in Singapore Chinese families, which suggests genetic heterogeneity.</p>