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Natural selection has played important roles in optimizing complex human adaptations. However, schizophrenia poses an evolutionary paradox during human evolution, as the illness has strongly negative effects on fitness, but persists with a prevalence of ~0.5% across global populations. Recent studies have identified numerous risk variations in diverse populations, which might be able to explain the stable and high rate of schizophrenia morbidity in different cultures and regions, but the questions about why the risk alleles derived and maintained in human gene pool still remain unsolved. Here, we studied the evolutionary pattern of a schizophrenia risk variant rs13107325 (P < 5.0 × 10(-8) in Europeans) in the SLC39A8 gene. We found the SNP is monomorphic in Asians and Africans with risk (derived) T-allele totally absent, and further evolutionary analyses showed the T-allele has experienced recent positive selection in Europeans. Subsequent exploratory analyses implicated that the colder environment in Europe was the likely selective pressures, ie, when modern humans migrated "out of Africa" and moved to Europe mainland (a colder and cooler continent than Africa), new alleles derived due to positive selection and protected humans from risk of hypertension and also helped them adapt to the cold environment. The hypothesis was supported by our pleiotropic analyses with hypertension and energy intake as well as obesity in Europeans. Our data thus provides an intriguing example to illustrate a possible mechanism for maintaining schizophrenia risk alleles in the human gene pool, and further supported that schizophrenia is likely a product caused by pleiotropic effect during human evolution.

MicroRNAs (miRNAs) are short non-coding RNAs which modulate gene expression by binding to complementary segments present in the 3′UTR of the mRNAs of protein coding genes. MiRNAs play very important roles in maintaining normal human body physiology conditions, meanwhile, abnormal miRNA expressions have been found related to many human diseases spanning from psychiatric disorders to malignant cancers. Recently, emerging reports have indicated that disturbed miRNAs expression contributed to the pathogenesis of recurrent pregnancy loss (RPL). In this study, we identified a new mutation site (+29A>G, position relative to pre-miR-125a) by scanning pri-miR-125a coding region in 389 Chinese Han RPL patients. This site was co-existed with two polymorphisms (rs12976445 and rs41275794) in patients heterogeneously and changed the predicted secondary structures of pri-miR-125a. Subsequent in vitro analysis indicated that the A>G mutation reduced mature miR-125a expression, and further led to less efficient inhibition of verified target genes. Functional analysis showed that mutant pri-mir-125a can enhance endometrial stromal cells (ESCs) invasive capacity and increase the sensitivity of ESCs cells to mifepristone. Moreover, we further analyzed the possible molecular mechanism by RIP-chip assay and found that mutant pri-mir-125a disturbed the expression of miR-125a targetome, the functions of which includes embryonic development, cell proliferation, migration and invasion. These data suggest that A>G mutation in pri-miR-125a coding region contributes to the genetic predisposition to RPL by disordering the production of miR-125a, which consequently meddled in gene regulatory network between mir-125a and mRNA.

Objective: Perilipin is a class of protein-coating lipid droplets in adipocytes and steroidogenic cells. Our purpose was to examine the association between common single-nucleotide polymorphisms (SNPs) at the perilipin (PLIN) locus and obesity, as well as related phenotypes, in unrelated American adults. Research Methods and Procedures: Four PLIN SNPs (PLIN 6209T>C, 11482G>A, 13041A>G, and 14995A>T) were typed in 734 white subjects (373 men and 361 women) attending a residential lifestyle intervention program. The baseline anthropometric and biochemical measures were used. Obesity was defined as BMI ≥ 30 kg/m2. Results: Multivariate analysis demonstrated that, in women, two of the SNPs (13041A>G, and 14995A>T) were significantly associated with percentage body fat (p = 0.016 for 13041A>G and p = 0.010 for 14995A>T) and waist circumference (p = 0.020 for 13041A>G and p = 0.045 for 14995A>T). Moreover, haplotype analysis using these two SNPs indicated that haplotypes A/T and G/T were both associated with significantly increased obesity risk (odds ratio = 1.76, 95% confidence interval 1.07 to 2.90 for haplotype A/T, and odds ratio = 1.73, 95% confidence interval 1.06 to 2.82 for haplotype G/T) when compared with haplotype A/A. No significant associations between PLIN variations and obesity were found in men. Discussion: Our data support the hypothesis that the PLIN locus may be a significant genetic determinant for obesity risk in whites and that women are more sensitive to the genetic effects of perilipin than men.

Although there are plenty of evidence that single-nucleotide polymorphisms (SNPs) that fall within coding sequences of genes are involved in recurrent pregnancy loss (RPL), it is still unknown whether the polymorphisms in microRNAs (miRNAs) are related with RPL. In this study, we established this kind of association by confirming significant differences in genotype distribution of rs41275794 (P= 0.0005) and rs12976445 (P= 0.001) within the pri-miR-125a in 217 Han Chinese patients of RPL compared with 431 controls. Based on this observation, two-locus haplotypes were constructed and the A-T haplotype was found to be associated with an increased risk of RPL (OR=2.84, 95%C.I. 1.98-4.07, P=0.0000000057). Further analysis showed that the levels of pre- and mature- miR-125a were down-regulated in the cells transfected with the A-T haplotype, which was consistent with in vivo detection that the level of mature miR-125a was lower in 30 pregnant women with A-T haplotype than that with G-C haplotype. During in vitro RNA processing assays, we found a similar decrease in the amount of pre-miR-125a and decline in binding capacity of nuclear factors to pri-miR-125a with A-T haplotype. More importantly, the reduction in miR-125a, as a consequence of A-T haplotype, further led to less efficient inhibition of target genes, LIFR and ERBB2, which play important roles in the embryo implantation and decidualization. Thus, our data collectively suggest that two common polymorphisms in pre-miR-125a might contribute to the genetic predisposition to RPL by disrupting the production of miR-125a, which consequently interfered in the expression and function of target genes of miR-125a.

There are dispute about the status of taxonomy among Astragalus membranaceus (Fisch.) Bge, A. membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao. and A. pallidipurpureus stat. nov. The varieties and taxa of the complex are still in need of revision. With molecular biology study used trnH-psbA intergenic region, the taxonomic revision of Radix Astragali has been made. A. pallidipurpureus stat. nov is suggested as a new species.

Objective: The variations in perilipin gene (PLIN) were previously associated with obesity and insulin sensitivity. We examined whether PLIN variability was associated with diabetes risk and obesity status modified such associations. Methods and Procedures: We conducted a nested case–control study of 431 incident cases of type 2 diabetes and 791 healthy control women from the Nurses' Health Study. Obesity was defined by BMI or waist circumference (central obesity). Results: In the sample of all participants, PLIN variations were not significantly associated with the incidence of diabetes. The central obesity status (by National Cholesterol Education Program Adult Treatment Panel III definition of waist circumference >35 inches) significantly interacted with PLIN polymorphisms in relation to diabetes risk (P for interaction = 0.027, 0.009, and 0.02 for rs2289487, rs8179043, and rs894160, respectively). In nonobese (central) women, carriers of rs2289487, rs8179043, and rs894160 had significantly greater risk of type 2 diabetes, adjusting for diabetes risk factors (odds ratio (OR) = 1.52, 1.03–2.25; 1.54, 1.07–2.23; and 1.57, 1.09–2.27, respectively). Haplotypes possessing the three polymorphisms were also significantly associated with diabetes risk (global test, P = 0.01). As compared with the most common haplotype 111, haplotype 222 and 211 (1 codes the common and 2 codes the minor alleles) were associated with 44% (OR = 1.44, 95% confidence interval (CI) 1.09–1.91; P = 0.01) and 70% (OR = 1.70, 95% CI 1.04–2.77; P = 0.03) greater risk, respectively. The PLIN variations were not significantly associated with the disease risk among women with central obesity. Discussion: Our data indicate that central obesity may modify the associations between PLIN variations and diabetes risk in women.

Interleukin-6 (IL-6, gene symbol IL6) is a proinflammatory cytokine. High circulating IL-6 levels have been associated with insulin resistance and greater risk of type 2 diabetes. Using a linkage disequilibrium (LD)-based approach, we sought to investigate the associations of the common polymorphisms comprehensively defining the genetic variability at the IL6 locus with diabetes risk. We conducted a case-control study of 2691 cases of type 2 diabetes (1692 women and 999 men) and 3237 control subjects (2238 women and 999 men) from the Nurses' Health Study and the Health Professional Follow-up Study. Pairwise LD analysis indicated that all the IL6 polymorphisms (rs2069827, rs1800797, rs1800795, rs1554606, rs2069849, rs2069861 and rs1818879) were in strong LD. We did not find significant associations between IL6 polymorphisms and the risk of type 2 diabetes in women or men, individually or in haplotypes. In addition, none of the IL6 polymorphisms was significantly associated with the plasma levels of IL-6 in the control subjects. Our meta-analysis of 5383 diabetes case and 12 069 controls indicated a null association between the best-studied 5' promoter polymorphism--174G>C (rs1800795)--and diabetes risk. Diversity in adiposity, age and sex could not account for the heterogeneity across different studies. In summary, the data in this study do not support substantial associations between the common polymorphisms in IL6 gene and circulating IL-6 levels and the risk of type 2 diabetes.

The apolipoprotein gene cluster (APOA1/C3/A4/A5) was recently associated with triglycerides (TG) and high-density lipoprotein cholesterol (HDL-C) in non-diabetic population. Little is known whether the variations in these genes affect lipid homeostasis in patients with type 2 diabetes. We examined the associations of 10 polymorphisms at APOA1/C3/A4/A5 gene cluster with blood lipids among 902 diabetic women. A linkage disequilibrium (LD) breakdown was observed between APOA5 and other genes. APOA5 S19W was associated with significantly higher fasting TG levels ( P =0.001). Two common haplotypes encompassing four APOA5 polymorphisms (SNP1, SNP2, S19W, and SNP3) were associated with 35.6mg/dL (haplotype 2212, APOA5*2, P =0.016) and 57.8mg/dL (haplotype 1121, APOA5*3, P =0.0002) higher fasting TG levels compared with the most common (haplotype 1111, APOA5*1), respectively. Adjustment for age, BMI, and other covariates did not appreciably change such associations. In addition, APOC3 promoter polymorphism −455T/C showed significant associations with fasting TG levels ( P =0.006), whereas APOA4 +347T/A showed significant associations with lower levels of HDL-C ( P =0.017). Our results indicate that the variability in APOA1/C3/A4/A5 gene cluster may affect TG and HDL levels in women with type 2 diabetes.

Perilipin is a lipid droplet surface protein present in adipocytes and steroidogenic cells. We examined five common single nucleotide polymorphisms (SNPs) at the perilipin (PLIN) locus (PLIN 6209C>T, 10171A>T, 11482G>A, 13041A>G, and 14995A>T) to investigate their association with obesity risk. The study population included 4,131 subjects of three ethnic groups (Chinese, Malay, and Indian) from Singapore. The prevalence of obesity in Malays and Indians was much higher than in Chinese. Moreover, in these groups the prevalence of obesity was three times higher in women than in men. Crude analysis indicated that haplotype 11212 (CAAAT) is shared by Malays and Indians and is significantly associated with increased obesity risk as compared to the most common haplotype 21111 (TAGAA): OR 1.65 (95% CI 1.11-2.46) in Malays and 1.94 (95% CI 1.06-3.53) in Indians. No associations between PLIN haplotypes and obesity risk were found in Chinese. To simplify the haplotype analyses we used a subgroup of three SNPs (11482G>A, 13041A>G, and 14995A>T) in positive linkage disequilibrium. These analyses revealed similar associations, showing that haplotypes XX212 (XXAAT) and XX222 (XXAGT) are associated with increased obesity risk in Malays OR 2.04 (95% CI 1.28-3.25) and 2.05 (95% CI 1.35-3.12) respectively, and that haplotype XXX212 (XXAAT) is significantly associated with increased obesity risk in Indians OR 2.16 (95% CI 1.10-4.26) after adjusting for covariates including age, sex, smoking, alcohol consumption, exercise, and diabetes status. Moreover, individual SNP analyses demonstrated that the PLIN 14995A>T SNP is the most informative single genetic marker for the observed haplotype association, being significantly associated with increased obesity risk in both Malays OR 2.28 (95% CI 1.45-3.57) and Indians OR 2.04 (95% CI 1.08-3.64). These results support the role of the PLIN locus as an ethnically dependent modulator of obesity risk in humans.