MyMedR

Displaying publications 1 - 20 of 440 in total

Abstract:

Sort:

Fulltext Genetic variability in selected date palm (Phoenix dactylifera L.) cultivars of United Arab Emirates using ISSR and DAMD markers

Purayil FT, Robert GA, Gothandam KM, Kurup SS, Subramaniam S, Cheruth AJ

3 Biotech, 2018 Feb;8(2):109.
PMID: 29430370 DOI: 10.1007/s13205-018-1108-3

Nine (9) different date palm (Phoenix dactylifera L.) cultivars from UAE, which differ in their flower timings were selected to determine the polymorphism and genetic relationship between these cultivars. Hereditary differences and interrelationships were assessed utilizing inter-simple sequence repeat (ISSR) and directed amplification of minisatellite DNA region (DAMD) primers. Analysis on eight DAMD and five ISSR markers produced total of 113 amplicon including 99 polymorphic and 14 monomorphic alleles with a polymorphic percentage of 85.45. The average polymorphic information content for the two-marker system was almost similar (DAMD, 0.445 and ISSR, 0.459). UPGMA based clustering of DAMD and ISSR revealed that mid-season cultivars, Mkh (Khlas) and MB (Barhee) grouped together to form a subcluster in both the marker systems. The genetic similarity analysis followed by clustering of the cumulative data from the DAMD and ISSR resulted in two major clusters with two early-season cultivars (ENg and Ekn), two mid-season cultivars (MKh and MB) and one late-season cultivar (Lkhs) in cluster 1, cluster 2 includes two late-season cultivars, one early-season cultivar and one mid-season cultivar. The cluster analysis of both DAMD and ISSR marker revealed that, the patterns of variation between some of the tested cultivars were similar in both DNA marker systems. Hence, the present study signifies the applicability of DAMD and ISSR marker system in detecting genetic diversity of date palm cultivars flowering at different seasons. This may facilitate the conservation and improvement of date palm cultivars in the future.

Matched MeSH terms: Polymorphism, Genetic
Genetic polymorphisms of TP53-binding protein 1 (TP53BP1) gene and association with breast cancer risk

Naidu R, Har YC, Taib NA

APMIS, 2011 Jul;119(7):460-7.
PMID: 21635553 DOI: 10.1111/j.1600-0463.2011.02753.x

In the present study, we evaluated the association between the TP53BP1 Glu353Asp and T-885G polymorphisms and breast cancer risk as well as with the clinicopathological characteristics of the patients. Genotyping of these polymorphisms was performed on 387 breast cancer patients and 252 normal and healthy women who had no history of any malignancy using PCR-RFLP method in a hospital-based Malaysian population. Breast cancer risk was not observed among women who were heterozygous (OR(adj) = 0.887; 95% CI, 0.632-1.245) or homozygous (OR(adj) = 1.083; 95% CI, 0.595-1.969) for Asp allele, and those carriers of Asp allele (OR(adj) = 0.979; 95% CI, 0.771-1.243). Similarly, women who were TG heterozygotes (OR(adj) = 1.181; 95% CI, 0.842-1.658) or GG homozygotes (OR(adj) = 1.362; 95% CI, 0.746-2.486) and carriers of G allele (OR(adj) = 1.147; 95% CI, 0.903-1.458) were not associated with increased risk of breast cancer. Asp allele genotype was significantly associated with ER negativity (p = 0.0015) and poorly differentiated tumours (p = 0.008), but G allele genotype was not associated with the clinicopathological characteristics. In conclusion, Glu353Asp and T-885G polymorphic variants might not have an influence on breast cancer risk, thus might not be potential candidates for cancer susceptibility. Glu353Asp variant might be associated with tumour aggressiveness as defined by its association with ER negativity and poorly differentiated tumours.

Matched MeSH terms: Polymorphism, Genetic*
On a new species of Dermatophagoides (D. neotropicalis) from house dust, producing both normal and heteromorphic males (Sarcoptiformes: Pyroglyphidae)

Fain A, Van Bronswijk JE

Acarologia, 1973 Sep;15(1):181-7.
PMID: 4794998
Matched MeSH terms: Polymorphism, Genetic
Molecular characterization and nonradioactive detection of beta-thalassemia in Malaysia

Fucharoen S, Fucharoen G, Ata K, Aziz S, Hashim S, Hassan K, et al.

Acta Haematol., 1990;84(2):82-8.
PMID: 2120891 DOI: 10.1159/000205034

The spectrum of beta-thalassemia mutations in Malaysia has been determined in 45 beta-thalassemia chromosomes using dot blot hybridization of the polymerase chain reaction amplified DNA and direct DNA sequencing. Eleven different molecular defects, including those previously detected in Chinese, Asian Indians, and American blacks, and a novel frameshift mutation causing beta zero-thalassemia were detected. Since this novel mutation, a T deletion in codon 15 creates a new restriction site for EcoRII enzyme; the mutation could be detected by EcoRII digestion of the appropriate amplified fragment. The results of the present study provide additional information on the molecular heterogeneity of beta-thalassemia in this population. We also demonstrated the nonradioactive detection method of the beta-thalassemia mutation based upon the digoxigenin-labeled oligonucleotide probes.

Matched MeSH terms: Polymorphism, Genetic
Genetic polymorphism in domain I of the apical membrane antigen-1 among Plasmodium knowlesi clinical isolates from Peninsular Malaysia

Fong MY, Wong SS, Silva JR, Lau YL

Acta Trop, 2015 Dec;152:145-150.
PMID: 26384455 DOI: 10.1016/j.actatropica.2015.09.009

The simian malaria parasite Plasmodium knowlesi is now recognized as a species that can cause human malaria. The first report of large scale human knowlesi malaria was in 2004 in Malaysia Borneo. Since then, hundreds of human knowlesi malaria cases have been reported in Southeast Asia. The present study investigates the genetic polymorphism of P. knowlesi DI domain of the apical membrane antigen-1 (AMA-1), a protein considered as a promising vaccine candidate for malaria. The DI domain of AMA-1 gene of P. knowlesi clinical isolates from Peninsular Malaysia was amplified by PCR, cloned into Escherichia coli, then sequenced and analysed. Ninety-seven DI domain sequences were obtained. Comparison at the nucleotide level against P. knowlesi strain H as reference sequence showed 21 synonymous and 25 nonsynonymous mutations. Nonetheless, nucleotide sequence analysis revealed low genetic diversity of the DI domain, and it was under purifying (negative) selection. At the amino acid level, 26 different haplotypes were identified and 2 were predominant haplotypes (H1, H2) with high frequencies. Phylogenetic analysis revealed that the 26 haplotypes could be clustered into 2 distinct groups (I and II). Members of the groups were basically derived from haplotypes H1 and H2, respectively.

Matched MeSH terms: Polymorphism, Genetic*
Recent Advances in the Genetics of Hypertension

Wei LK, Au A, Teh LK, Lye HS

Adv Exp Med Biol, 2017;956:561-581.
PMID: 27957710 DOI: 10.1007/5584_2016_75

Hypertension is a silent killer worldwide, caused by both genetic and environmental factors. Until now, genetic and genomic association studies of hypertension are reporting different degree of association on hypertension. Hence, it is essential to gather all the available information on the reported genetic loci and to determine if any biomarker(s) is/are significantly associated with hypertension. Current review concluded the potential biomarkers for hypertension, with regards to electrolyte and fluid transports, as well as sodium/potassium ions homeostasis, which are supported by the results of case-controls and meta-analyses.

Matched MeSH terms: Polymorphism, Genetic*
Fulltext Isolation and characterization of microsatellite markers for an important tropical tree, Aquilaria malaccensis (Thymelaeaceae)

Tnah LH, Lee CT, Lee SL, Ng KK, Ng CH, Nurul-Farhanah Z, et al.

Am J Bot, 2012 Nov;99(11):e431-3.
PMID: 23108468 DOI: 10.3732/ajb.1200165

Aggressive collections and trade activities in recent decades have resulted in heavy pressure on the natural stands of Aquilaria malaccensis and concerns over its long-term survival potential. To aid DNA profiling and assessment of its genetic diversity, microsatellite markers were developed for the species.

Matched MeSH terms: Polymorphism, Genetic
Fulltext Isolation and characterization of microsatellite loci in an endangered palm, Johannesteijsmannia lanceolata (Arecaceae)

Ang CC, Lee SL, Lee CT, Tnah LH, Zakaria RM, Ng CC

Am J Bot, 2011 May;98(5):e117-9.
PMID: 21613176 DOI: 10.3732/ajb.1000494

Microsatellite markers were developed for Johannesteijsmannia lanceolata to assess the genetic diversity and mating system of this alarmingly endangered species.

Matched MeSH terms: Polymorphism, Genetic
Fulltext Microsatellite markers of an important medicinal plant, Eurycoma longifolia (Simaroubaceae), for DNA profiling

Tnah LH, Lee CT, Lee SL, Ng KK, Ng CH, Hwang SS

Am J Bot, 2011 May;98(5):e130-2.
PMID: 21613180 DOI: 10.3732/ajb.1000469

Microsatellite markers of an important medicinal plant, Eurycoma longifolia (Simaroubaceae), were developed for DNA profiling and genetic diversity studies.

Matched MeSH terms: Polymorphism, Genetic
Kin-structured migration: causes and consequences

Fix AG

Am J Hum Biol, 2004 Jul-Aug;16(4):387-94.
PMID: 15214057

Migration among local populations classically has been seen as the principal process retarding genetic microdifferentiation. However, as Sewall Wright pointed out long ago, migration may also act as a random differentiating force. In fact, when migrants comprise a biological kin group, migration may be considered a component of genetic drift. The causes of kin-structured migration (KSM) lie in the common, if not universal, tendency for kin to associate and cooperate. However, similar to genetic drift, KSM has its greatest effect in smaller populations and is most apparent in low-density fission-fusion societies such as the Yanomamo of South America and the Semai of Malaysia, and less salient in higher density, low-mobility populations such as those of the New Guinea Highlands. The evolutionary consequences of KSM begin with increased genetic variation among populations. Such intergroup variation provides a basis for group selection. The origin of larger-scale geographic differentiation can arise from kin-structured migrant groups colonizing new regions. Waves of colonizing kin-structured founder groups may produce gene frequency clines, mimicking demic diffusion and natural selection. Finally, because kin structuring reduces the effective size of a population, it may be speculated that the extremely small effective size inferred for ancestral populations of Homo sapiens may be an artifact of kin-structured demographically larger populations.

Matched MeSH terms: Polymorphism, Genetic
Genetic factors and malaria in the Temuan

Baer A, Lie-Injo LE, Welch QB, Lewis AN

Am J Hum Genet, 1976 Mar;28(2):179-88.
PMID: 817597

The jungle habitat of the Temuan aborigines harbors a variety of infectious diseases, the most notable being malaria. Our study of 15 genetic systems in the Temuan revealed substantial polymorphism and within-population genetic diversity. The polymorphisms for Hb beta, G6PD, and El are of interest in regard to genetic adaptation to malaria. Among the polymorphisms investigated we conclude that G6PD deficiency and elliptocytosis are likely to have malaria-resistant effects as evidenced by their low association with malarial parasitemia or their higher frequency in adults than in children. These findings suggest that the malarial habitat of the Temuans is livable in the long range sense for them because of the cluster of malaria-resistant alleles in their gene pool (G6PD)-, El, and possibly, but not tested here because of its low frequency, Hb beta E). The same condition probably holds for the Semai, the nearest aborigine neighbors of the Temuan (although the Semai have not been tested for malarial parasitemia and for these polymorphisms simultaneously), since the Semai have substantial Hb betaE, G6PD-, and El. The Temuan have a cultural identity system of rituals, beliefs, and certain aspects of language which effectively isolates them genetically from Malays and other nonaborigines. This system hinders the dilution of the malaria-resistant alleles of the Temuan gene pool with the malaria-susceptible alleles of the nonaborigine gene pools.

Matched MeSH terms: Polymorphism, Genetic*
Erythrocyte and leukocyte phosphoglucomutase in Chinese

Lie-Injo Luan Eng, Lopez CG, Poey-Oey Hoey Giok

Am J Hum Genet, 1968 Mar;20(2):101-6.
PMID: 5643177
Matched MeSH terms: Polymorphism, Genetic
Reduction in arterial stiffness with angiotensin II antagonism and converting enzyme inhibition. A comparative study among malay hypertensive subjects with a known genetic profile

Rehman A, Ismail SB, Naing L, Roshan TM, Abdul Rahman AR

Am J Hypertens, 2007 Feb;20(2):184-9.
PMID: 17261465 DOI: 10.1016/j.amjhyper.2006.07.015

BACKGROUND: Data comparing the effect of losartan and perindopril on aortic stiffness among hypertensive subjects without A(1166)C polymorphism was not available.
METHODS: The short-term and long-term effects of losartan (50 mg) and perindopril (4 mg) on aortic stiffness measured as carotid femoral pulse wave velocity (PWV) were compared in 39 middle-aged Malay subjects with mild-to-moderate hypertension in a 4-month, double-blind, randomized, controlled, parallel-design study.
RESULTS: Four-month treatment with both drugs showed a significant reduction in blood pressure (BP) (P < .005) and PWV (P < .05) as compared to the baseline. On the other hand 1-month treatment showed a significant reduction in BP only in perindopril group (P < .05) but not in the losartan group. There was no significant reduction in pulse pressure and PWV after 1 month treatment by both drugs. No significant difference was seen in reduction in BP after 1 month and 4 months treatment between the two drugs. Similarly no significant difference was seen in reduction in PWV between the two drugs after 1 month (P = .613) and 4 months (P = .521) of treatment. Reduction in PWV by losartan (r = 0.470) and perindopril (r = 0.457) correlated significantly only with reduction in DBP (P < .05) and remained significant even after controlling for reduction in DBP (P < .05). Reduction in PWV by both losartan and perindopril was independent of reduction in BP by these drugs.
CONCLUSIONS: These results showed that long-term treatment with losartan shows similar pressure independent reduction in PWV as perindopril among Malay hypertensive subjects with a homogenous "AA" genotype for angiotensin II type 1 receptor and may serve as a suitable alternative to perindopril.

Matched MeSH terms: Polymorphism, Genetic
Fulltext Striatin Gene Polymorphic Variants Are Associated With Salt Sensitive Blood Pressure in Normotensives and Hypertensives

Gupta T, Connors M, Tan JW, Manosroi W, Ahmed N, Ting PY, et al.

Am J Hypertens, 2017 Dec 08;31(1):124-131.
PMID: 28985281 DOI: 10.1093/ajh/hpx146

BACKGROUND: Understanding the interactions between genetics, sodium (Na+) intake, and blood pressure (BP) will help overcome the lack of individual specificity in our current treatment of hypertension. This study had 3 goals: expand on the relationship between striatin gene (STRN) status and salt-sensitivity of BP (SSBP); evaluate the status of Na+ and volume regulating systems by striatin risk allele status; evaluate potential SSBP mechanisms.
METHODS: We assessed the relationship between STRN status in humans (HyperPATH cohort) and SSBP and on volume regulated systems in humans and a striatin knockout mouse (STRN+/-).
RESULTS: The previously identified association between a striatin risk allele and systolic SSBP was demonstrated in a new cohort (P = 0.01). The STRN-SSBP association was significant for the combined cohort (P = 0.003; β = +5.35 mm Hg systolic BP/risk allele) and in the following subgroups: normotensives, hypertensives, men, and older subjects. Additionally, we observed a lower epinephrine level in risk allele carriers (P = 0.014) and decreased adrenal medulla phenylethanolamine N-methyltransferase (PNMT) in STRN+/- mice. No significant associations were observed with other volume regulated systems.
CONCLUSIONS: These results support the association between a variant of striatin and SSBP and extend the findings to normotensive individuals and other subsets. In contrast to most salt-sensitive hypertensives, striatin-associated SSBP is associated with normal plasma renin activity and reduced epinephrine levels. These data provide clues to the underlying cause and a potential pathway to achieve, specific, personalized treatment, and prevention.

Matched MeSH terms: Polymorphism, Genetic/genetics
Maternal lineage of Nicobari pig (Sus scrofa nicobaricus) correlated with migration of Nicobarese, a native tribal population of Andaman and Nicobar Islands, India

De AK, Sawhney S, Ponraj P, Muthiyan R, Muniswamy K, Ravi SK, et al.

Anim Biotechnol, 2023 Apr;34(2):156-165.
PMID: 34310265 DOI: 10.1080/10495398.2021.1950742

Nicobari pig is reared by Nicobarese, a native tribal population of Andaman and Nicobar Islands. Nicobari pig has maintained its genetic identity due to geographical isolation. This communication is the first report on maternal inheritance of Nicobari pigs. DNA polymorphism data showed seven haplotypes. D-loop sequence information and mitogenome analysis were able to earmark Nicobari pigs to Asian clade. The domestication process of pigs and its expansion pattern help to understand human migration pattern. Based on this hypothesis, this communication elucidates the probable origin of Nicobarese. Earlier studies indicated that Nicobarese had genetic affinities to races distributed in China, Malaysia and Thailand. Our data on maternal inheritance of Nicobari pig correlates with the data on migration of Nicobarese. Moreover, we could establish a novel connection of Nicobarese with people of Northeastern parts of India, Philippines and Vietnam through phylogenetic signal and geographical provenance of Nicobari pig. We further concluded that migration of Nicobarese happened during Western route of migration (WRM) ∼4000 years before present. Therefore, we propose one wave hypothesis of peopling of Nicobar based on our study and existence of Ausrtroasiatic language, Mon-Khmer in these islands.

Matched MeSH terms: Polymorphism, Genetic*
The red cell 'X'-protein system in goats: evidence for a third allele in a Malaysian breed

Hasima N, Dhaliwal SS, Mukherjee TK

Anim. Genet., 1988;19(1):37-41.
PMID: 3377277

Genetic polymorphism of the 'X'-protein in red cells from Malaysian Katjang goats was demonstrated by starch gel electrophoresis at pH 7.3. Two new phenotypes were observed, suggesting that one new allele is involved. A new nomenclature for the 'X'-protein system in goats is proposed.

Matched MeSH terms: Polymorphism, Genetic*
Fulltext Adiponectin and resistin gene polymorphisms in association with their respective adipokine levels

Lau CH, Muniandy S

Ann. Hum. Genet., 2011 May;75(3):370-82.
PMID: 21323646 DOI: 10.1111/j.1469-1809.2010.00635.x

Single nucleotide polymorphisms (SNPs) at the adiponectin and resistin loci are strongly associated with hypoadiponectinemia and hyperresistinemia, which may eventually increase risk of insulin resistance, type 2 diabetes (T2DM), metabolic syndrome (MS), and cardiovascular disease. Real-time PCR was used to genotype SNPs of the adiponectin (SNP+45T>G, SNP+276G>T, SNP+639T>C, and SNP+1212A>G) and resistin (SNP-420C>G and SNP+299G>A) genes in 809 Malaysian men (208 controls, 174 MS without T2DM, 171 T2DM without MS, 256 T2DM with MS) whose ages ranged between 40 and 70 years old. The genotyping results for each SNP marker was verified by sequencing. The anthropometric clinical and metabolic parameters of subjects were recorded. None of these SNPs at the adiponectin and resistin loci were associated with T2DM and MS susceptibility in Malaysian men. SNP+45T>G, SNP+276G>T, and SNP+639T>C of the adiponectin gene did not influence circulating levels of adiponectin. However, the G-allele of SNP+1212A>G at the adiponectin locus was marginally associated (P= 0.0227) with reduced circulating adiponectin levels. SNP-420C>G (df = 2; F= 16.026; P= 1.50×10(-7) ) and SNP+299G>A (df = 2; F= 22.944; P= 2.04×10(-10) ) of the resistin gene were strongly associated with serum resistin levels. Thus, SNP-420C>G and SNP+299G>A of the resistin gene are strongly associated with the risk of hyperresistinemia in Malaysian men.

Matched MeSH terms: Polymorphism, Genetic*
The effects of three factor VII polymorphisms on factor VII coagulant levels in healthy Singaporean Chinese, Malay and Indian newborns

Quek SC, Low PS, Saha N, Heng CK

Ann. Hum. Genet., 2006 Nov;70(Pt 6):951-7.
PMID: 17044869

Factor VII (FVII) is an independent risk factor for coronary artery disease. Three polymorphisms of the factor VII gene (F7) were studied in a group of healthy newborns comprising 561 Chinese, 398 Malays and 226 Asian Indians from Singapore. The allele frequencies of 3 polymorphisms (R353Q, Promoter 0/10bp Del/Ins and Intron 7) in the FVII gene were ascertained through genotyping by polymerase chain reaction and restriction digestion of amplified fragments. In Chinese the minor allele frequencies are Q: 0.04, Ins: 0.03, R7: 0.44; Malays, Q: 0.06, Ins: 0.10, R7: 0.41; and Indians, Q: 0.25, Ins: 0.23, R7: 0.43. Strong linkage disequilibrium (Delta > 0.7) is observed between the 0/10 bp and the R353Q sites in all ethnic groups. We conclude that: (i) the prevalence of the minor Q and Ins alleles of the R353Q and 0/10 bp polymorphisms are significantly higher in the Indian newborns than the Chinese and Malays; (ii) the Q allele is significantly associated (p = 0.01) with a lower plasma FVII coagulant level in the Indian and Malay neonates; and this polymorphism explains up to 3.8% of the variance in FVII coagulant levels; (iii) there is no significant difference in allele frequencies of the three polymorphisms between neonates with and without family histories of CAD.

Matched MeSH terms: Polymorphism, Genetic*
The association of mitochondrial DNA 5178 C > a polymorphism with plasma lipid levels among three ethnic groups

Lal S, Madhavan M, Heng CK

Ann. Hum. Genet., 2005 Nov;69(Pt 6):639-44.
PMID: 16266403

Mitochondria are eukaryotic cytoplasmic organelles responsible for oxidative phosphorylation. The C to A nucleotide transversion in the NADH dehydrogenase subunit 2 (MT-ND2) coding region of mitochondrial DNA has been reported to be associated with plasma lipid levels, adult onset diseases and longevity. We have examined the role of this polymorphism in relation to plasma lipid levels and age in a total of 713 healthy individuals belonging to 3 ethnic groups in Singapore. The frequency of the A allele was significantly higher (p < 0.05) among the Chinese (0.15) in comparison to the Malays (0.05) and Indians (0.02). No significant difference in the frequency of the allele was observed between healthy and coronary artery disease subjects, and between age-stratified subjects. We found that the polymorphism is significantly associated in an ethnic- and gender-specific manner with plasma apoB levels in the Chinese males (p < 0.05). This is the first epidemiological report of the mt5178 C > A polymorphism and its association with plasma lipid levels in Asian populations outside Japan.

Matched MeSH terms: Polymorphism, Genetic*
Apolipoprotein E (APOE) allele distribution in the world. Is APOE*4 a 'thrifty' allele?

Corbo RM, Scacchi R

Ann. Hum. Genet., 1999 Jul;63(Pt 4):301-10.
PMID: 10738542

Apolipoprotein E (APOE = gene, apoE = protein) plays a central role in plasma lipoprotein metabolism and in lipid transport within tissues. The APOE shows a genetic polymorphism determined by three common alleles, APOE*2, APOE*3, APOE*4 and the product of the three alleles differs in several functional properties. APOE is involved in the development of certain pathological conditions. In particular, the APOE*4 allele is a risk factor for susceptibility to coronary artery disease (CAD) and Alzheimer's Disease (AD). In the present study we analyzed the APOE allele distribution in the world. The APOE*3 is the most frequent in all the human groups, especially in populations with a long-established agricultural economy like those of the Mediterranean basin (0.849-0.898). The frequency of APOE*4, the ancestral allele, remains higher in populations like Pygmies (0.407) and Khoi San (0.370), aborigines of Malaysia (0.240) and Australia (0.260), Papuans (0.368), some Native Americans (0.280), and Lapps (0.310) where an economy of foraging still exists, or food supply is (or was until the recent past) scarce and sporadically available. The APOE*2 frequency fluctuates with no apparent trend (0.145-0.02) and is absent in Native Americans. We suggest that the APOE*4, based on some functional properties it has and on its distribution among human populations, could be identified as a 'thrifty' allele. The exposure of APOE*4 to the contemporary environmental conditions (Western diet, longer lifespans) could have rendered it a susceptibility allele for CAD and AD. The absence of the association of APOE*4 with CAD and AD in Sub-Saharan Africans, and its presence in African Americans, seems to confirm this hypothesis.

Matched MeSH terms: Polymorphism, Genetic

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links