The rapidly declining Golden-winged Warbler (Vermivora chrysoptera) is of conservation concern owing in part to hybridization with the closely related Blue-winged Warbler (V. pinus). These species hybridize extensively in eastern North America and over the past century the Blue-winged Warbler has displaced the Golden-winged Warbler from substantial regions of its historic breeding range. A previous study suggested that these genetic interactions result in rapid and asymmetric introgression of Blue-winged Warbler mitochondrial DNA (mtDNA) into Golden-winged phenotype populations within the zones of contact, but more recent and extensive surveys have documented a more complex pattern of genetic interchange between these taxa. We surveyed mtDNA/phenotype associations in 104 individuals of known phenotype drawn from two locations with different histories of contact and found substantial variation between sites in the extent of introgression. Where both species have co-existed for more than a century, we found evidence of bi-directional introgression and the long-term persistence of Golden-winged mtDNA haplotypes. At the leading edge of the northward expansion of Blue-winged Warblers, we found predominantly Golden-winged Warbler mtDNA haplotypes in both Golden-winged and hybrid-phenotype individuals. Across both sites, genetic swamping does not appear to be occurring via the early immigration of Blue-winged Warbler females into populations dominated by Golden-winged Warbler phenotypes. Instead, the differing patterns of mitochondrial introgression may be driven by the relative local population sizes of the parental species coupled with subtle between-species differences in mate choice and habitat preferences.

Assortative mating is a universal feature of human societies, and individuals from ethnically diverse populations are known to mate assortatively based on similarities in genetic ancestry. However, little is currently known regarding the exact phenotypic cues, or their underlying genetic architecture, which inform ancestry-based assortative mating. We developed a novel approach, using genome-wide analysis of ancestry-specific haplotypes, to evaluate ancestry-based assortative mating on traits whose expression varies among the three continental population groups – African, European, and Native American – that admixed to form modern Latin American populations. Application of this method to genome sequences sampled from Colombia, Mexico, Peru, and Puerto Rico revealed widespread ancestry-based assortative mating. We discovered a number of anthropometric traits (body mass, height, and facial development) and neurological attributes (educational attainment and schizophrenia) that serve as phenotypic cues for ancestry-based assortative mating. Major histocompatibility complex (MHC) loci show population-specific patterns of both assortative and disassortative mating in Latin America. Ancestry-based assortative mating in the populations analyzed here appears to be driven primarily by African ancestry. This study serves as an example of how population genomic analyses can yield novel insights into human behavior.

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In this publication we present a fast method of diagnosing the most common polymorphisms of BRCA1 and BRCA2 genes in Poland – C61G [c.300T>G], C64R [c.190T>C], 4153delA [c.4035delA], 3819del5 [c.3700_3704delGTAAA], and C5972T [c.5744C>T]. Our procedure is based on the use of the cleaved amplified polymorphic sequences (CAPS) and artificially created restriction site (ACRS) PCR techniques. The precise selection of appropriate primer sequences and restriction enzymes enabled specific cuts of DNA fragments. The final quantity and size of the obtained products depend on the presence or the absence of the mutations. The obtained results are unambiguous and do not have to be confirmed by sequencing. The methods of detection of the C61G, C64R, 4153delA, 3819del5, and C5972T mutations in the BRCA1 and BRCA2 genes described by us do not require a sequencing process, which is more expensive, time-consuming and associated with numerous errors. The technique developed by us enables the use of simple electrophoresis for accurate detection of the presence or absence of a specific mutation. Our procedures are fast, precise and unambiguous.