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Protein Polymorphisms (protein + polymorphism)
Selected AbstractsSEXUAL CONFLICT AND PROTEIN POLYMORPHISMEVOLUTION, Issue 7 2004Ralph Haygood Abstract Sexual conflict, where male and female reproductive interests differ, is probably widespread and often mediated by male or sperm proteins and female or egg proteins that bind to each other during mating or fertilization. One potential consequence is maintenance of polymorphism in these proteins, which might result in reproductive isolation between sympatric subpopulations. I investigate the conditions for polymorphism maintenance in a series of mathematical models of sexual conflict over mating or fertilization frequency. The models represent a male or sperm ligand and a female or egg receptor, and they differ in whether expression of either protein is haploid or diploid. For diploid expression, the conditions imply that patterns of dominance, which involve neither overdominance nor un-derdominance, can determine whether polymorphism is maintained. For example, suppose ligand expression is diploid, and consider ligand alleles L1 and L2 in interactions with a given receptor genotype; if L1/L1 males are fitter than L2/L2 males in these interactions, then polymorphism is more likely to be maintained when L1/L2 males more closely resemble L1/L1 males in these interactions. Such fitter-allele dominance might be typical of a ligand or its receptor due to their biochemistry, in which case polymorphism might be typical of the pair. [source] Serotonin Transporter Protein Polymorphism and Harm Avoidance Personality in Migraine without AuraHEADACHE, Issue 6 2006Jeong Wook Park MD Objective.,To investigate polymorphisms in the serotonin transporter protein gene and harm avoidance personality dimension in patients with migraine without aura (MWOA). Background.,The serotonin transporter protein is a key modulator of serotonergic synaptic neurotransmission. Two polymorphic regions of the gene for serotonin transporter protein have been found, and are associated with variations in the functional activity of serotonin caused by differing transcriptional efficiency. The harm avoidance (HA) personality trait may also be heritable and associated with altered serotonergic neurotransmitter activity. Design.,We amplified the polymorphism in the promoter of serotonin transporter protein (5-HTTLPR) and the variable number of tandem repeats polymorphism within intron 2 (VNTR) using the polymerase chain reaction and performed genotype polymorphism analyses in 97 patients with MWOA and 100 healthy controls. We investigated serotonin-related personality traits by evaluating the HA personality dimension using a tridimensional questionnaire. Results.,The genotype frequencies and allele distributions of 5-HTTLPR did not differ between patients with MWOA and controls. The VNTR genotype STin2.12/STin2.12 was significantly more common in patients with MWOA (90%) than in controls (77%; P= .017). Patients with MWOA also had HA scores (21.9 ± 6.4) significantly higher than those of controls (16.3 ± 6.1; P < .001). Conclusions.,Serotonergic activity might be involved in the development of MWOA and VNTR of serotonin transporter gene might be one of the genetically contributing factors. [source] Y chromosome haplotyping in Scandinavian wolves (Canis lupus) based on microsatellite markersMOLECULAR ECOLOGY, Issue 8 2001A.-K. Sundqvist Abstract The analysis of mitochondrial DNA sequences has for a long time been the most extensively used genetic tool for phylogenetic, phylogeographic and population genetic studies. Since this approach only considers female lineages, it tends to give a biased picture of the population history. The use of protein polymorphisms and microsatellites has helped to obtain a more unbiased view, but complementing population genetic studies with Y chromosome markers could clarify the role of each sex in natural processes. In this study we analysed genetic variability at four microsatellite loci on the canid Y chromosome. With these four microsatellites we constructed haplotypes and used them to study the genetic status of the Scandinavian wolf population, a population that now contains 60,70 animals but was thought to have been extinct in the 1970s. In a sample of 100 male wolves from northern Europe we found 17 different Y chromosome haplotypes. Only two of these were found in the current Scandinavian population. This indicates that there should have been at least two males involved in the founding of the Scandinavian wolf population after the bottleneck in the 1970s. The two Scandinavian Y chromosome haplotypes were not found elsewhere in northern Europe, which indicates low male gene flow between Scandinavia and the neighbouring countries. [source] Population genetic dynamics in the French Guiana regionAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 1 2009Stéphane Mazières Three sets of genetic markers (blood group plus protein polymorphisms, mitochondrial DNA, and Y-chromosome) were compared in four French Guiana and one Brazilian Amerindian populations. Spearman's rank correlation coefficient between five gene diversity statistics and historical or present-day population sizes showed significant values, indicating loss of diversity due to population bottlenecks. The three sets of markers furnished distinct admixture estimates, and the blood group plus protein polymorphisms could have overestimated the European contribution to their gene pool. Correspondence analysis distinguished the coastal from the interior populations, possibly reflecting past migration events. Am. J. Hum. Biol., 2009. © 2008 Wiley-Liss, Inc. [source] Novel prion protein polymorphisms in cattleANIMAL GENETICS, Issue 5 2003A. Takasuga No abstract is available for this article. [source] Milk protein polymorphisms in cattle (Bos indicus), mithun (Bos frontalis) and yak (Bos grunniens) breeds and their hybrids indigenous to BhutanANIMAL SCIENCE JOURNAL, Issue 5 2010Tashi DORJI ABSTRACT In the current study, milk protein variation was examined in cattle (Bos indicus), mithun (Bos frontalis), yak (Bos grunniens) and their hybrid populations in Bhutan to estimate genetic variability, conduct genetic characterization and assess the possibility of gene flow between mithun and cattle. Isoelectric focusing of 372 milk samples from 11 populations detected four molecular types of ,- lactoglobulin (A, B, E and M), five molecular types of ,S1 -casein (A, B, C, E and X) and three molecular types of k -casein (A, B and X). Mithun and yak shared alleles but were found to exhibit different allele frequencies for the proteins studied. The degree of genetic variability within populations was measured by average heterozygosity and ranged from 24,40% in cattle, 26% for yak and 33% for mithun. We also resolved the traditional mithun and cattle hybridization system via principal component analysis. Our results suggested secondary introgression of mithun genes to the village Thrabum population, and a close genetic relationship between Bhutanese indigenous cattle and Indian cattle. [source] Identification of ovalbumin phenotypes of the Asian indigenous chicken populations using polymerase chain reaction-restriction fragment length polymorphismANIMAL SCIENCE JOURNAL, Issue 5 2003Keiji KINOSHITA ABSTRACT Three electrophoretic variations (AA, BB and AB) of ovalbumin controlled by codominant alleles OvA and OvB have been observed in various chicken populations. We compared nucleotide sequences of the open reading frame between two alleles of ovalbumin gene. The difference between the two alleles was found as a non-synonymous substitution of asparagine to aspartic acid as a result of AAT to GAT point mutation at position 8032,8034 in exon 8. We developed polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) protocol in combination with Mbo I restriction endnuclease mapping for the detection of this substitution. By the PCR-RFLP the allelic frequency of the OvB was estimated to be within the range of 0.000,0.150 in 11 Asian indigenous chicken populations and 0.000 in four improved breeds used in the present study. Gene frequency, estimated by PCR-RFLP in the present study, paralleled that obtained by protein polymorphisms of egg white. Thus, this study provides, for the first time, information of the occurrence of ovalbumin allele OvA and OvB in Asian indigenous chicken populations. [source] | ||||||||||