Evaluating DNA tests of motherless cases using a Philippine genetic database.

BACKGROUND: In 5 percent of paternity determination cases, only DNA samples from the alleged father and child pairs are tested. The absence of the mother's DNA increases the probability of false paternity inclusions, which affects laboratories that use a limited number of DNA markers. The effect of coincidental matches between unrelated individuals on DNA tests of motherless cases was determined using the Philippine population genetic database of the National Capital Region (NCR). STUDY DESIGN AND METHODS: Seven short tandem repeat (STR) markers were used, namely HUMvWA, HUMTH01, HUMCSF1PO, HUMFOLP23, D8S306, HUMFES/FPS, and HUMF13A01. Values of the probability of paternity with (W) and without a mother (W(-mother)) were determined using the equation W = cumulative likelihood ratio/cumulative likelihood ratio + 1). These values were determined for 50 volunteer families and compared with values calculated from randomly matched pairs in a reference NCR population database. RESULTS: The W and W(-mother) values of the 50 families range from 96.48 to 99.99 percent and 79.76 to 99.99 percent, respectively. In the NCR database, 195 coincidental matches in seven STR loci out of 5253 possible pairs (3.71%) were detected with W(-mother) values ranging from 12.47 to 99.83 percent. Of these, 53 and 10 random pairs have W(-mother) greater than 95.0 and 99.0 percent, respectively. CONCLUSION: W was higher than W(-mother) in the 50 families. However, the existence of unrelated individuals in the NCR database that randomly matched at seven STR loci and that has W(-mother) values greater than 99.0 percent highlights the need for greater precaution when dealing with motherless cases.

Philippine population database at nine microsatellite loci for forensic and paternity applications.

Allele frequency distributions for a Filipino population from the National Capital Region (NCR) were determined for eight STR loci: HUMF13A01, HUMFES/FPS, HUMvWA, HUMFOLP23, HUMD8S306, HUMCSFIPO, HUMTPOX and HUMTHO1; and a VNTR locus: D1S80. Statistical analysis showed that the nine loci showed no deviations from Hardy-Weinberg and linkage equilibrium rules. The average power of paternity exclusion for the nine loci is 0.9962 and the discriminating power is 1-2 x 10(-9). The data obtained from this study will be used as reference data for forensic DNA typing in the Philippines.

Allele frequency distributions of the polymorphic STR loci HUMVWA, HUMFES, HUMF13A01 and the VNTR D1S80 in a Filipino population from Metro Manila.

Allele frequency distributions at the short tandem repeat (STR) loci HUMVWA, HUMFES, HUMF13A01 and of the variable number of tandem repeat (VNTR) locus D1S80 were determined in a Filipino population from Metro Manila (103 individuals) by use of the polymerase chain reaction (PCR) followed by polyacrylamide gel electrophoresis (PAGE). The exact test demonstrated that all four loci had no deviations from Hardy-Weinberg equilibrium (HWE) with the only reservation that the exact test p-value for F13A01 is weak. The discriminating power is 0.82 for D1S80, and the expected exclusion chance is 0.85 for F13A01, 0.83 for FES, and 0.93 for VWA. The observed heterozygosity rates are 0.63 for D1S80, 0.66 for F13A01, 0.67 for FES, and 0.80 for VWA. The exact test for independance between all loci gave a p-value of 0.0195. This is the first time that Filipino population data of DNA loci of forensic importance are reported.

Two new 17 α-hydroxyprogesterone transformation products fromNocardia DSM 43298.

Two new products: 9,10-seco-1,3,5(10)-pregnatrien-3,17 a-dihydroxy-9,20-dione and 9,10-seco-1,3,5(10)-pregnatrien-3,17a,20-triol-9-one, have been isolated as 17 α-hydroxyprogesterone transformation products fromNocardia DSM 43298. The structures were established by spectroscopic methods.