Alterations in gene expression of calcium handling proteins in patients with chronic atrial fibrillation / 中国医学科学院学报

<p><b>OBJECTIVE</b>To discuss the role of calcium-overloading in initiation and maintenance of atrial fibrillation (AF).</p><p><b>METHODS</b>The right atrial appendages were obtained from 14 patients with AF and 12 patients with sinus rhythm. The mRNA expression of proteins influencing the calcium homeostasis was measured by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and normalized to the mRNA level of glyceraldehyde-3- phosphate dehydrogenase. The left atrial diameter (LAD), mitral valvular area (MVOA), and systolic pulmonary arterial pressure were obtained by echocardiography before surgery.</p><p><b>RESULTS</b>Compared to sinus rhythm group, the mRNA levels of L-type calcium channel alc, sarcoplasmic reticulum (SR), calcium adenosine triphosphatase (Ca2+ -ATPase), and ryanodine receptor type-2 (R(Y) R2) were significantly decreased (P < 0.01); the mRNA level of inositol triphosphate receptor type-1 (IP3R1) was significantly increased (P < 0.05). No changes in the mRNA expression of phospholamban and calsequestrin were observed between two groups (P > 0.05). Correlations were found between MVOA and mRNA levels of LVDC-Calc, SR Ca2+ -ATPase (r = 0.719, P = 0.004; r = 0.625, P = 0.017). The mRNA level of SR Ca2+ -ATPase was negatively correlated with LAD (r = -0.573, P = 0.032).</p><p><b>CONCLUSIONS</b>Calcium loading may be responsible for the occurrence and maintenance of AF, and abnormal regulation in the mRNA expression may be the molecular mechanism of intracellular Ca2+ overload. The progressive nature of AF involves structural change.</p>

Comparative study of APOB gene 3'VNTR polymorphisms between natural longevity and controls in Uighur nationality / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the association of polymorphisms in the apolipoprotein B gene (APOB) 3'variable number of tandem repeat with natural longevity in the Xinjiang Uighur nationality people.</p><p><b>METHODS</b>Totally 191 healthy individuals over 90 years and 53 individuals aged 65-70 years were recruited among Xinjiang Uighur population, the nationality, gender and living area were matched. Genotyping was performed using polymerase chain reaction-sequence specific primer(PCR-SSP) and PCR-sequencing.</p><p><b>RESULTS</b>Fourteen alleles were found in the Xinjiang Uighur nationality population. The frequency of HVE36 and HVE42 in the natural longevity group were significantly higher than that in the control group (both P<0.05) and HVE44, HVE46, HVE48 and HVE58 were only found in the natural longevity group. However, the frequency of HVE26, HVE30 and HVE34 were markedly lower in the natural longevity group compared to the control group. Logistic regression analyses revealed that allele L and the genotypes LL were positively associated with age, whereas the allele S and genotype SS were negatively associated with age (both P<0.05). Each allele consists of 15 bp tandem repeats with rich-AT by PCR-sequencing.</p><p><b>CONCLUSION</b>These results indicate that the S allele, and SS genotype are frail factors in China Uighur natural longevity people, whereas allele L and genotypes LL are protective factors.</p>

Polymorphism of apolipoprotein E gene and natural longevity in the Xinjiang Uighur people: an association study / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the distribution of polymorphisms of apolipoprotein E(apoE) gene and its relation to natural longevity in the Xinjiang Uighur people.</p><p><b>METHODS</b>Using polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP), the authors obtained data from centenarians(n=42), 90-year-old people (n=102), 65-70-year-old people (n=70) and controls(n=53).</p><p><b>RESULTS</b>The frequencies of apoE genotypes epsilon 3/4, epsilon 3/3 and epsilon 2/3 were 2.4%, 69.0% and 23.8% respectively in the centenarian group, and the frequencies of their epsilon 4, epsilon 3 and epsilon 2 alleles were 1.2%, 82.1% and 16.7%. The frequencies of genotype epsilon 3/4 and epsilon 4, epsilon 3 allele in the centenarian group were significantly lower than those in controls(P< 0.01), whereas the frequencies of genotype epsilon 2/3 and epsilon 2 allele in the centenarian group were significantly higher than those in controls(P< 0.01). Longevity was noted to be positively correlated with epsilon 2 and negatively correlated with epsilon 4.</p><p><b>CONCLUSION</b>This relationship reflects a genetic influence on differential survival and may point to pleiotropic age-dependent effects on longevity.</p>

Relationship of I/D polymorphism of angiotensin converting enzyme gene with hypertension in Xinjiang Kazakh isolated group / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate whether the insertion/deletion(I/D) polymorphism in the angiotensin converting enzyme(ACE) gene is associated with essential hypertension in Xinjiang Kazakh isolated population.</p><p><b>METHODS</b>The study covered 201 hypertensives and 151 normotensive controls in Xinjiang Barlikun Kazakh population. The I/D polymorphism of ACE gene was determined by polymerase chain reaction.</p><p><b>RESULTS</b>The frequencies of D and I in the hypertensive group (0.44 and 0.56, respectively) were not significantly different from the controls(0.39 and 0.61, respectively, P=0.16). The frequencies of ACE genotypes of DD, ID, and II were 0.18, 0.52, 0.30 in hypertensives respectively and 0.17, 0.43, 0.40 in control group respectively. There was no significant difference in genotypes between hypertensive group and normotensive group (P=0.14).</p><p><b>CONCLUSION</b>The results suggested that the I/D polymorphism of ACE gene might not be associated with hypertension in the Kazakh population of Xinjiang Barlikun area.</p>