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At least 19 recordsLinked to original sources
PubMed1979

[Physiological polymorphism of a grass frog population. III. The effect of the season on the phenotypic manifestation of frog polymorphism by the level of muscle tissue thermostability].

A study was made of the phenotypical manifestation of physiological polymorphism of the population of the grass frog by the heat resistance level of m. interphalangealis in different seasons. In autumn (starting from the 2nd half of October), throughout winter, and in summer the polymorphism of frogs is well expressed, whereas in spring (during the reproduction period) and in the first half of October (during the migration of animals to the places of hibernation) the polymorphism appears to be hidden. The latter phenomenon is due to differences in the pattern of individual seasonal changes in the heart resistance of muscles in individuals of different groups.

Animals↗
PubMed1979

Polymorphism of apolipoprotein E. III. Effect of a single polymorphic gene locus on plasma lipid levels in man.

The two autosomal codominant alleles of the Apo E-N/D polymorphism, Apo En and Apo Ed, have a considerable influence on plasma lipid levels and distribution in man. Serum cholesterol levels are highest in phenotype Apo E-N, intermediate in phenotype Apo E-ND, and low in phenotype Apo E-D. Contrary VLDL-cholesterol is highest in phenotype Apo E-D, intermediate in heterozygotes, and lowest in phenotype Apo E-N. Serum-triglyceride, VLDL-triglyceride and the ratio of VLDL-cholesterol/serum-triglyceride are also intermediate in phenotype Apo E-ND between the two opposite homozygous groups. 10% of heterozygous Apo E-ND subjects exhibited a beta-VLDL subfraction compared to 0.8% in phenotype Apo E-N and 100% in Apo E-D. Hence the three phenotypic groups exhibit metabolic differences in vivo, and the gene Apo Ed has a mild dyslipoproteinemic effect even in a single dose. The Apo E-N/D polymorphism may therefore be a major influence on the occurrence of arteriosclerotic vascular disease in man.

Adult↗
PubMed1977

Frequency of RFA colour polymorphisms of human acrocentric chromosomes in caucasians: interrelationship with QFQ polymorphisms.

One hundred normal caucasians were studied by sequential QFQ and RFA in order to estimate the type and frequency of variation. Colour variants were classified into 1 of 6 colours by RFA and intensity variations into 1 of 5 levels by QFQ. The interrelationship between QFQ and RFA variants was also examined. It was found that there was no consistent relationship between negative or brilliant QFQ variants and the various colours observed with RFA. RFA colour polymorphisms for chromosomes 13, 14, 15, 21 and 22 were 33.0, 38.0, 28.0, 50.0 and 24.5% while QFQ frequencies were 56.5, 10.0, 10.0, 15.5 and 10.0% respectively. RFA is especially useful in studying the inheritance of chromosome 21.

Adult↗
PubMed1978

[Physiological polymorphism of a population of the common frog. II. The polymorphism of the type of muscle tissue heat resistance in stress].

A study was made of the dynamics in the heat resistance of m. interphalangealis of individual grass frogs under stress. The response of muscle tissue to injury can be differentiated into three types according to the initial heat resistance level: increase, decrease and phase change of the resistance. The pattern of response of muscle tissue of individual frogs to stress is one of manifestationss of physiological polymorphism of the population.

Animals↗
PubMedDate not supplied

Polymorphism of indomethacin. Part II. Identification and rapid determination of polymorphic forms of indomethacin by IR spectrometry.

A procedure is described, which make it possible to determine the content of individual polymorphic forms of indomethacin in their mixture by IR spectrometry. IR spectra recorded in the range of 1600--1800 cm-1 have been used in the determinations. The method is especially useful for analytical control of the technological process of preparing the most pharmacologically active-gemma-form of indomethacin.

Indomethacin↗
PubMed1978

[Physiological polymorphism in a population of the common frog. I. The polymorphism of a population of the common frog for the trait of muscle tissue heat resistance].

A study was made of heat resistance (36+/-0.2 degrees C) of m. interphalangealis of the third finger of a hind extremity in animals of one population of Rana temporaria L. living on the boundary between Leningrad region and Pskov region. Within this population, the existence of three groups of individuals differing in heat resistance levels of their m. interphalangealis is postulated. This conclusion is based on the distribution curve of heat resistance values and on the application of the probit-method. The distribution of the frequency of occurrence of individuals in these three groups follows Hardy-Weinberg's equation.

Animals↗
PubMed2026

Evaluating Associations Between Ankylosing Spondylitis, Torque Teno Virus and Polymorphisms in Interleukin 6 and Vitamin D Receptor Genes.

The etiology of ankylosing spondylitis (AS) is complex and not yet fully understood. Interleukin-6 (IL-6), vitamin D and the vitamin D receptor (VDR) play an important role in modulating immune response, and Torque teno virus is considered a marker of immune status. This case-control study aimed to investigate the predisposition to AS. A total of 85 patients with AS and 100 clinically healthy individuals were included. VDR polymorphisms (rs2228570, rs1544410, rs7975232, rs731236) were genotyped using the PCR-RFLP technique, while for the IL-6 -174 G>C (rs1800795) polymorphism the tetra-primer ARMS-PCR technique was used. The presence of TTV was detected using the hemi-nested PCR technique. Our findings indicate a statistically significant association between TTV and AS (p = 0.035). C allele of both rs1800795 polymorphism in main groups (p = 0.027) and rs731236 polymorphism in women subgroups (p = 0.036) may be linked to an increased susceptibility to AS. However, none of these associations reach statistical significance after Bonferroni correction. Furthermore, within female subgroups, a significant association was found between the T allele of rs1544410 polymorphism and AS (p = 0.000038, corrected p = 0.00076). A significant association was also observed between the TT genotype of rs2228570 polymorphism, TTV and AS (p = 0.029). Haplotype analysis revealed that certain VDR haplotypes may confer either a protective effect against AS or an increased risk of developing the condition. Notably, rs1544410 polymorphism or a linked polymorphism may influence AS susceptibility. In conclusion, our data suggest that TTV and VDR polymorphisms may be associated with an increased risk of developing AS, indicating that these markers could potentially be used in the future for earlier diagnosis and more targeted treatment of the disease.

Torque teno virus↗
PubMed2025

Association of MTHFD1 G1958A (rs2236225) gene polymorphism with the risk of congenital heart disease: a systematic review and meta-analysis.

BACKGROUND: We did this study to better clarify the correlations of methylenetetrahydrofolate dehydrogenase 1 (MTHFD1)-G1958A (rs2236225) gene polymorphism with the risk of congenital heart diseases (CHD) and its subgroups. METHODS: Relevant articles were searched in PubMed, Web of Science, Cochrane Library, Embase, CNKI, VIP database and Wanfang DATA until October 2023. We will use odds ratios (ORs) and 95% confidence intervals (CIs) to examine the potential associations of MTHFD1- G1958A gene polymorphism with CHD and its subgroups. RESULTS: We included a total of 9 eligible studies, encompassing 1917 children with CHD, 1863 healthy children, 1717 mothers of the children with CHD and 1666 mothers of healthy children. In our study, the meta-analysis of fetal group revealed no significant association between any of the five genetic models for the MTHFD1-G1958A polymorphism and the risk of CHD. Subgroup analysis showed that associations between the MTHFD1-G1958A polymorphism and Tetralogy of Fallot (TOF) risk in the homozygote model (AA vs. GG, OR = 2.82, 95%CI [1.16, 6.86], P = 0.02) and recessive model (AA vs. GG + GA, OR = 3.09, 95%CI [1.36, 7.03], P = 0.007). In addition, the MTHFD1-G1958A polymorphism was associated with the risk of CHD in racial subgroup, increasing the risk of CHD in Caucasians. In maternal analysis, 2 genetic models of MTHFD1-G1958A polymorphism increased the risk of CHD: the heterozygote model (GA vs. GG, OR = 1.22, 95%CI [1.04, 1.42], P = 0.01), and the dominance model (GA + AA vs. GG, OR = 1.17, 95%CI [1.01, 1.34], P = 0.03). CONCLUSIONS: The fetal MTHFD1-G1958A (rs2236225) gene polymorphism increase their risk of TOF. The maternal MTHFD1-G1958A polymorphism has a strong correlation with the risk of CHD, and there are racial differences in this correlation. Compared with GG genotype, the GA genotype increases the risk of CHD.

Humans↗
PubMed2024

Association between OX40L polymorphism and type 2 diabetes mellitus in Iranians.

INTRODUCTION: Diabetes mellitus (DM) is one of the leading causes of morbidity and mortality worldwide. It is a multifactorial disease that genetic and environmental factors contribute to its development. The aim of the study was to investigate the association of OX40L promoter gene polymorphisms with type 2 diabetes mellitus (T2DM) in Iranians. MATERIALS AND METHODS: Three hundred and sixty-eight subjects including 184 healthy subjects and 184 T2DM patients were enrolled in our study. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was applied to detect genotype and allele frequencies of rs3850641, rs1234313 and rs10912580. In addition, SNPStats web tool was applied to estimate haplotype frequency and linkage disequilibrium (LD). RESULTS: The distribution of tested polymorphisms was statistically different between the T2DM patients and healthy subjects (P&#x2009;<&#x2009;0.01). rs1234313 AG (OR&#x2009;=&#x2009;0.375, 95% CI&#x2009;=&#x2009;0.193-0.727, P&#x2009;=&#x2009;0.004) and rs10912580 AG (OR&#x2009;=&#x2009;0.351, 95% CI&#x2009;=&#x2009;0.162-0.758, P&#x2009;=&#x2009;0.008) genotypes were associated with the decreased risk of T2DM in Iranians. Moreover, our prediction revealed that AAG (OR&#x2009;=&#x2009;0.46, 95% CI= (0.28-0.76), P&#x2009;=&#x2009;0.0028) and GAG (OR&#x2009;=&#x2009;0.24, 95% CI= (0.13-0.45), P&#x2009;<&#x2009;0.0001) haplotypes were related to the reduced risk of the disease. However, the tested polymorphisms had no effect on biochemical parameters and body mass index (BMI) in the patient group (P&#x2009;>&#x2009;0.05). CONCLUSION: Our findings revealed that OX40L promoter gene polymorphisms are associated with T2DM. Moreover, genotype and allelic variations were related to the decreased risk of T2DM in Iranians. Further studies are recommended to show whether these polymorphic variations could affect OX40/OX40L interaction or OX40L phenotype.

Adult↗
PubMed1975

A survey of isozyme polymorphism in a Drosophila melanogaster natural population.

A survey of biochemical polymorphism among glucose- and non-glucose-metabolizing enzymes was carried out on the June 1973 collection from the South Amherst, Mass. Drosophila melanogaster natural population. Polymorphic levels are among the highest recorded for this species; polymorphism among glucose-metabolizing enzymes did not differ significantly from that among non-glucose-metabolizing enzymes. Two loci, G6Pd on the X and Est-6 on the 3rd chromosome, displayed significant excesses of heterozygotes. Adh on the 2nd and Idh, Odh and Ao on the 3rd chromosome showed significant heterozygote deficiencies. Idh is ten map units to the left of Est-6, Odh twelve map units to the right and Ao is seven units beyond Odh. Temperatures in the two-week June period prior to collection were exceedingly variable. Daily high/low ranged between 76 degrees/40 degrees and 97 degrees/65 degrees F. These results support the findings of Frydenberg and Simonsen (1973) that in some populations glucose-metabolizing enzymes tend to be as polymorphic as non-glucose-metabolizing ones. They also add to the evidence obtained from other plant and animal populations that increased biochemical polymorphism is associated with more variable and/or colder climates. The increase may in part be due to increased polymorphism among glucose-metabolizing enzymes. Comparisons utilizing published data on other D. melanogaster populations and on D. robusta indicate a clinal increase in heterozygosity among glucose-metabolizing enzymes as one moves northward.

Animals↗
PubMed2026

Association of Vitamin D Receptor Gene Polymorphism (FokI) with Susceptibility to Musculoskeletal Tuberculosis: A Case-Control Study from Central India.

AIM AND BACKGROUND: Musculoskeletal tuberculosis (MSKTB) constitutes a significant proportion of extra-pulmonary tuberculosis (TB), particularly in developing countries like India. While host genetic factors are known to influence susceptibility to TB, the Vitamin D receptor (VDR) gene, particularly the FokI polymorphism, has been implicated in immune regulation and susceptibility to pulmonary and extra-pulmonary TB, data on genetic predisposition to MSKTB remain limited. The present study aimed to investigate the role of the VDR FokI gene polymorphism in determining susceptibility to MSKTB. MATERIALS AND METHODS: This study included 110 patients with confirmed MSKTB and 112 controls without TB, recruited from a tertiary care institution over a 3-year period. Clinical and demographic data were obtained. Genomic DNA was extracted from peripheral venous blood samples, and VDR FokI polymorphism was detected using polymerase chain reaction-based restriction fragment length polymorphism analysis. Genotype and allele frequencies were compared using a Chi-square test, and odds ratios (OR) with 95% confidence intervals (CI) were calculated. RESULTS: The ff genotype was significantly more frequent in cases (17.3%) compared to controls (9.8%) and was associated with increased risk of MSKTB (OR = 2.30, 95% CI: 1.03-5.15, P = 0.04). The polymorphic f allele frequency was also significantly higher in cases than controls (38.2% vs. 28.1%; OR = 1.58, 95% CI: 1.05-2.37, P = 0.023). However, the dominant and recessive genetic models showed a non-significant association. Demographically, MSKTB was more common among females, individuals from rural backgrounds, those of lower socioeconomic status, and those with low body mass index. CONCLUSION: The VDR FokI polymorphism, particularly the ff genotype and f allele, is associated with increased susceptibility to MSKTB. These findings highlight the potential role of genetic factors in MSKTB and may aid in identifying at-risk populations.

FokI polymorphism↗
PubMed2026

Genetic polymorphism in Plasmodium falciparum MSPDBL1 and MSPDBL2 and their impact on B- and T-cell immunodominant epitopes in Brazilian malaria-endemic areas.

Merozoite Surface Protein Duffy Binding-like 1 and 2 (MSPDBL1 and MSPDBL2) are involved in erythrocyte invasion by Plasmodium falciparum. Antibodies targeting PfMSPDBL1 and PfMSPDBL2 show strong opsonizing and growth-inhibitory activities, supporting their potential as asexual blood-stage vaccine candidates. Given that the extensive genetic diversity of P. falciparum contributes to immune evasion, identifying polymorphisms in regions encoding PfMSPDBL1 and PfMSPDBL2 is essential to assess their relevance as vaccine targets. In this study, we investigated polymorphisms in the pfmspdbl1 and pfmspdbl2 genes and their impact on potentially antigenic regions within the Duffy Binding-like (DBL) and Secreted Polymorphic Antigen Associated with Merozoite (SPAM) domains. Blood samples were collected from 47 P falciparum-infected individuals from three malaria-endemic areas of the Brazilian Amazon. Genomic DNA was extracted, PCR-amplified, and sequenced. Intrapopulation genetic diversity and Tajima's D values were estimated using bioinformatics tools. Linear B- and T-cell epitopes were predicted using BCPreds and IEDB (Immune Epitope Database), respectively. Two and thirty-two polymorphisms were identified in pfmspdbl1 within the SPAM and DBL domains, respectively, whereas pfmspdbl2 presented two polymorphisms across both domains and a 12 bp insertion in the SPAM domain. Tajima's D values were positive across domains, except for the DBL domain of pfmspdbl2 in M&#xe2;ncio Lima. Fifteen B-cell and fifteen T-cell epitopes were predicted, with polymorphisms in three B-cell epitopes affecting Vaxijen scores. Together, these findings reveal contrasting evolutionary patterns between PfMSPDBL1 and PfMSPDBL2, with potential implications for antigenicity, and highlight PfMSPDBL2 as a potential candidate for further evaluation in multicomponent blood-stage malaria vaccine development.

Genetic diversity↗
PubMed1978

Identification of a new serum protein polymorphism as transferrin.

By isoelectric focusing at pH 3.5--9.5, Kühnl and Spielmann (1977) recently demonstrated a new genetically determined serum protein polymorphism designated 'Hpa' because of an apparently specific reaction with antihaptoglobin. In this study the polymorphism was reproduced, but the components were found to focus at pH 5.8, which is different from the pI of haptoglobin, and immunologic relation to haptoglobin could not be confirmed. Using pure transferrin as a reference, the results of isoelectric focusing, crossed immunoelectrophoresis, and immunofixation indicated that the polymorphic components were identical to transferrin. This polymorphism does not correspond to the already known transferrin polymorphism, as the two usual genes, tentatively designated Tf1 and Tf2, in my population sample (n = 132) were 0.19 and 0.81, and, further, all individuals except three in the sample belong to type Tf-C.

Denmark↗
PubMed1977

Genetic studies of the Macushi and Wapishana Indians. I. Rare genetic variants and a "private polymorphism' of esterase A.

Blood samples from 509 Macushi and 623 Wapishana Amerindians of of Northern Brazil and Southern Guyana have been analyzed with reference to the occurrence of rare variants and genetic polymorphisms of the following 25 systems: (i) Erythrocyte enzymes: acid phosphatase-1, adenosine deaminase, adenylate kinase-k, carbonic anhydrase-1, carbonic anhydrase-2, esterase A1,2,3, esterase D, galactose-1-phosphate uridyltransferase, isocitrate dehydrogenase, lactate dehydrogenase, malate dehydrogenase, nucleoside phosphorylase, peptidase A, peptidase B, phosphoglucomutase 1, phosphoglucomutase 2, phosphogluconate dehydrogenase, phosphohexoseisomerase, triosephosphate isomerase and (ii) Serum proteins: albumin, ceruloplasmin, haptoglobin, hemoglobin A2 and transferrin. Fifteen different rare variants were detected, involving 11 of these systems. In addition, a previously undescribed variant of ESA 1,2,3 which achieves polymorphic proportions in both these tribes is described. Excluding this variant, the frequency of rare variants is 1.1/1000 in 12510 determinations in the Macushi and 4.7/1000 in 15396 determinations in the Wapishana. The ESA 1,2,3 polymorphism was not observed in 382 Makiritare, 232 Yanomama, 146 Piaroa, 404 Cayapo, 190 Kraho and 112 Moro. Irregularities in the intratribal distribution of this polymorphism in the Macushi and Wapishana render a decision as to the tribe of origin impossible at present. Gene frequencies are also given for previously described polymorphisms of 5 systems: haptoglobin, phosphoglucomutase 1, erythrocyte acid phosphatase, esterase D, and galactose-1-phosphate-uridyl-transferase.

Blood Proteins↗