Multiple myeloma (MM) is two- to three-fold more common in African Americans (AAs) compared to European Americans (EAs). This striking disparity, one of the highest of any cancer, may be due to underlying genetic predisposition between these groups. There are multiple unique cytogenetic subtypes of MM, and it is likely that the disparity is associated with only certain subtypes. Previous efforts to understand this disparity have relied on self-reported race rather than genetic ancestry, which may result in bias. To mitigate these difficulties, we studied 881 patients with monoclonal gammopathies who had undergone uniform testing to identify primary cytogenetic abnormalities. DNA from bone marrow samples was genotyped on the Precision Medicine Research Array and biogeographical ancestry was quantitatively assessed using the Geographic Population Structure Origins tool. The probability of having one of three specific subtypes, namely t(11;14), t(14;16), or t(14;20) was significantly higher in the 120 individuals with highest African ancestry (≥80%) compared with the 235 individuals with lowest African ancestry (<0.1%) (51% vs. 33%, respectively, p value = 0.008). Using quantitatively measured African ancestry, we demonstrate a major proportion of the racial disparity in MM is driven by disparity in the occurrence of the t(11;14), t(14;16), and t(14;20) types of MM.

Sperms, collected following sexual activity of volunteers, were processed to isolate high-molecular weight deoxyribonucleic acid (DNA). These DNA samples were digested with particular restriction endonucleases and analyzed with probes that recognize polymorphic DNA regions within the human genome. The pattern of restriction fragment length polymorphisms (RFLP) detected by this test is identical to that observed with DNA prepared from blood of the male sexual partner. Therefore, RFLP analysis can be used to exclude or to determine the probable identity of an assailant in rape cases.

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Purpose:The aim of the study was to evaluate the diagnostic accuracy of an informatics-based, noninvasive, prenatal paternity test using array-based single-nucleotide polymorphism measurements of cell-free DNA isolated from maternal plasma.Methods:Blood samples were taken from 21 adult pregnant women (with gestational ages between 6 and 21 weeks), and a genetic sample was taken from the corresponding biological fathers. Paternity was confirmed by genetic testing of the infant, products of conception, control of fertilization, and/or preimplantation genetic diagnosis during in vitro fertilization. Parental DNA samples and maternal plasma cell-free DNA were amplified and analyzed using a HumanCytoSNP-12 array. An informatics-based method measured single-nucleotide polymorphism data, confirming or rejecting paternity. Each plasma sample with a sufficient fetal cell-free DNA fraction was independently tested against the confirmed father and 1,820 random, unrelated males.Results:One of the 21 samples had insufficient fetal cell-free DNA. The test correctly confirmed paternity for the remaining 20 samples (100%) when tested against the biological father, with P values of <10−4. For the 36,400 tests using an unrelated male as the alleged father, 99.95% (36,382) correctly excluded paternity and 0.05% (18) were indeterminate. There were no miscalls.Conclusion:A noninvasive paternity test using informatics-based analysis of single-nucleotide polymorphism array measurements accurately determined paternity early in pregnancy.

Fifty known siblings and fifty unrelated pairs were genotyped using the ABI Identifiler STR system and sibship indices computed for each pair. Combined sibship indices (CSIs) for the known siblings ranged from less than 10 to greater than 1 billion. CSIs for the unrelated pairs ranged from 4.5 × 10 −8 to 0.12. In the known sibling group the percentage of loci where both alleles matched was approximately 40%, while the percentage of loci where neither matched was approximately 10%. In the non-sibling group, the percentage of loci where both alleles matched was approximately 6%, while the percentage of loci where neither matched was approximately 45%. Interestingly, the percentage of loci where a single allele matched was the same in both the known siblings and unrelated pairs, approximately 50%.