Association of PvuII and XbaI polymorphisms on estrogen receptor alpha (ESR1) gene to changes into serum lipid profile of post-menopausal women: Effects of aging, body mass index and breast cancer incidence

Metabolic Syndrome, BMI, and Polymorphism of Estrogen Receptor-α in Peri- and Post-Menopausal Polish Women

The study aimed to investigate the association between the estrogen receptor alpha (ERα) polymorphism and the prevalence of metabolic syndrome (MetS) and obesity, as well as the coexistence of MetS and obesity, in peri- and post-menopausal Polish women. The study group consisted of 202 peri-menopausal and 202 post-menopausal women. ERα polymorphism: Xba I and Pvu II, MetS, BMI, and serum estrogen concentration were analyzed. MetS was found in 29% of the peri-menopausal women and in 21% of the post-menopausal women. BMI did not significantly differ between the peri- and post-menopausal women (≈42% were normal weight, ≈40% were overweight, and ≈18% were obese), (p = 0.82). Serum estrogen concentration in the peri-menopausal women was 91 ± 75 pg/mL, while that in the post-menopausal women was 17 ± 9. pg/mL, on average. Peri-menopausal women with AA and TT genotypes of the ERα polymorphism have a lower risk of obesity and MetS and the co-existence of obesity and MetS, whereas those women with the G or C allele have a higher risk of those health problems.

Pubertal mammary gland development is a key determinant of adult mammographic density

Mammographic density refers to the radiological appearance of fibroglandular and adipose tissue on a mammogram of the breast. Women with relatively high mammographic density for their age and body mass index are at significantly higher risk for breast cancer. The association between mammographic density and breast cancer risk is well-established, however the molecular and cellular events that lead to the development of high mammographic density are yet to be elucidated. Puberty is a critical time for breast development, where endocrine and paracrine signalling drive development of the mammary gland epithelium, stroma, and adipose tissue. As the relative abundance of these cell types determines the radiological appearance of the adult breast, puberty should be considered as a key developmental stage in the establishment of mammographic density. Epidemiological studies have pointed to the significance of pubertal adipose tissue deposition, as well as timing of menarche and thelarche, on adult mammographic density and breast cancer risk. Activation of hypothalamic-pituitary axes during puberty combined with genetic and epigenetic molecular determinants, together with stromal fibroblasts, extracellular matrix, and immune signalling factors in the mammary gland, act in concert to drive breast development and the relative abundance of different cell types in the adult breast. Here, we discuss the key cellular and molecular mechanisms through which pubertal mammary gland development may affect adult mammographic density and cancer risk.

Genetic and non-genetic factors associated with the phenotype of exceptional longevity & normal cognition

In this study, we split 2156 individuals from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) data into two groups, establishing a phenotype of exceptional longevity & normal cognition versus cognitive impairment. We conducted a genome-wide association study (GWAS) to identify significant genetic variants and biological pathways that are associated with cognitive impairment and used these results to construct polygenic risk scores. We elucidated the important and robust factors, both genetic and non-genetic, in predicting the phenotype, using several machine learning models. The GWAS identified 28 significant SNPs at p-value [Formula: see text] significance level and we pinpointed four genes, ESR1, PHB, RYR3, GRIK2, that are associated with the phenotype though immunological systems, brain function, metabolic pathways, inflammation and diet in the CLHLS cohort. Using both genetic and non-genetic factors, four machine learning models have close prediction results for the phenotype measured in Area Under the Curve: random forest (0.782), XGBoost (0.781), support vector machine with linear kernel (0.780), and [Formula: see text] penalized logistic regression (0.780). The top four important and congruent features in predicting the phenotype identified by these four models are: polygenic risk score, sex, age, and education.

Estrogen receptor 1 gene polymorphisms (PvuII and XbaI) are associated with type 2 diabetes in Palestinian women

Background

Type 2 diabetes mellitus (T2DM) is a multifactorial disease where both genetic and environmental factors contribute to its pathogenesis. The PvuII and XbaI polymorphisms of the estrogen receptor 1 (ESR1) gene have been variably associated with T2DM in several populations. This association has not been studied in the Palestinian population. Therefore, the aim of this study was to investigate the association between the PvuII and XbaI variants in the ESR1 and T2DM and its related metabolic traits among Palestinian women.

Methods

This case-control study included 102 T2DM and 112 controls in which PvuII and XbaI variants of the ESR1 gene were genotyped using amplicon based next generation sequencing (NGS).

Results

Allele frequencies of both PvuII and XbaI variants were not significantly different between patients and control subjects (P > 0.05). In logestic regression analysis adjusted for age and BMI, the ESR1 PvuII variant was associated with risk of T2DM in three genotypic models (P < 0.025) but the strongest association was observed under over-dominant model (TT+CC vs. TC) (OR = 2.32, CI [1.18-4.55] adjusted P = 0.013). A similar but non-significant trend was also observed for the ESR1 XbaI variant under the over-dominant model (AA+GG vs. AG) (OR = 2.03, CI [1.05-3.95]; adjusted P = 0.035). The frequencies of the four haplotypes (TA, CG, CA, TG) were not significantly different in the T2DM patients compared with control group (P > 0.025). Among diabetic group, an inverse trend with risk of cardio vascular diseases was shown in carriers of CG haplotype compared to those with TA haplotype (OR = 0.28, CI [0.09-0.90]; adjusted P = 0.035). Further, stratified analyses based on ESR1 PvuII and XbaI genotypes revealed no evidence for association with lipid levels (TC, TG, HDL, LDL).

Conclusions

This is the first Palestinian study to conclude that ESR1 PuvII and XbaI variants may contribute to diabetes susceptibility in Palestinian women. Identification of genetic risk markers can be used in defining high risk subjects and in prevention trials.

Estrogen receptor α and β gene polymorphism in relation to bone mineral density and lipid profile in Northeast Indian women

Estrogen regulates bone homeostasis and has a cardio-protective effect. Its physiological functions are mediated through receptors (ER) whose expression can be regulated by presence or absence of polymorphisms. However, the association between ER polymorphisms and BMD as well as lipids are inconsistent. The aim of the study was to investigate whether polymorphisms in ESR are associated with bone mineral density (BMD) and lipids in a cohort of Indian women. We studied PvuII, XbaI polymorphisms in ESR1 and AluI, RsaI polymorphisms in ESR2 genes and their association with bone mineral density (BMD) and lipids in premenopausal (n = 293, mean age: 33.01 ± 5.23 years) and postmenopausal (n = 145, mean age: 56.91 ± 7.1 years) women from Northeast India. AluI and RsaI polymorphisms in ESR2 gene were associated with BMD in postmenopausal women. Logistic regression analysis adjusted for age, BMI, tobacco and alcohol consumption revealed that xx genotype in XbaI polymorphism is associated with osteopenia at spine (OR = 3.3, 95% CI = 1.067-10.204) in postmenopausal women suggesting that allele X is protective (OR = 0.419, 95% CI = 0.177-0.991). Genotype aa in AluI polymorphism, seemed to be protective (OR = 0.092 for osteopenia; OR = 0.152 for osteoporosis) at spine whereas A allele was associated with osteopenia at femur (OR = 2.123, 95% CI = 1.079-4.166) in postmenopausal women. Allele r of RsaI polymorphism, was associated with osteoporosis at spine (OR = 3.222, 95% CI = 1.302-7.96). Thus, AIuI polymorphism of ESR2 gene was associated with spinal and femoral BMD whereas RsaI only with spinal BMD in postmenopausal women and ESR genotypes were not associated with lipids.

Association of rs2234693 and rs9340799 polymorphisms of estrogen Receptor-1 gene with radiographic defined knee osteoarthritis: A meta-analysis

OBJECTIVE

To evaluate the association of ESR1 rs2234693 and rs9340799 polymorphisms with radiographic defined knee osteoarthritis (OA), a case-control and meta-analysis was performed.

METHODS

A total of 25 case-control studies with 7,144 cases and 8,468 controls with were included.

RESULTS

There was a significant association between rs2234693 polymorphism and radiographic knee OA under heterozygote model (CT vs. TT: OR = 1.164, 95% CI 1.053-1.286, p = 0.003). However, there was no association between rs9340799 and radiographic knee OA. In subgroup analysis by ethnicity, risk estimates were not augmented.

CONCLUSIONS

Our results showed that the ESR1 rs2234693 polymorphism might be associated with radiographic defined knee OA, but not rs9340799.

Interplays of estrogen receptor alpha gene rs2234693 with post-traumatic stress disorder influence serum glucose and lipids profiles in Chinese adolescents

Both post-traumatic stress disorder (PTSD) and estrogen receptor alpha (ESR1) gene rs2234693 were reported to influence serum glucose and lipids profiles. However, their interactions on serum glucose and lipids profiles have not been reported. A total of 708 Chinese Han high school students were recruited at 6th months after the 2008 Wenchuan Earthquake. Serum concentrations of fasting blood glucose (FBG), fasting blood insulin (FBI), total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) were detected. Body mass index (BMI) and homeostatic model assessment of insulin resistance (HOMA-IR) were calculated. PTSD was assessed by the PTSD Checklist Civilian Version (PCL-C). Variants of ESR1 rs2234693 was analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analyses and verified by DNA sequencing. The male subjects with PTSD had a trend of higher FBG (p = 0.077) and significantly higher FBI and HOMA-IR than male controls. The PTSD subjects had significantly higher levels of FBG, FBI, HOMA-IR and HDL-C than the controls only in the male C allele carriers irrespective of adjustment for age and BMI. In the male controls group, the C allele carriers had significantly lower HDL-C than the TT homozygotes regardless of adjustment for age and BMI. In female PTSD group, the C allele carriers had significantly higher TC/HDL-C and LDL-C/HDL-C than the TT homozygotes after adjustment for age and BMI. These results suggest the interplays of ESR1 rs2234693 with PTSD influence serum glucose and lipids profiles with a gender dependent manner.

Inverse association between estrogen receptor-α DNA methylation and breast composition in adolescent Chilean girls

Background

Estrogen receptor-α (ER-α) is a transcriptional regulator, which mediates estrogen-dependent breast development, as well as breast tumorigenesis. The influence of epigenetic regulation of ER-α on adolescent breast composition has not been previously studied and could serve as a marker of pubertal health and susceptibility to breast cancer. We investigated the association between ER-α DNA methylation in leukocytes and breast composition in adolescent Chilean girls enrolled in the Growth and Obesity Cohort Study (GOCS) in Santiago, Chile. Breast composition (total breast volume (BV; cm³), fibroglandular volume (FGV; cm³), and percent fibroglandular volume (%FGV)) was measured at breast Tanner stage 4 (B4). ER-α promoter DNA methylation was assessed by pyrosequencing in blood samples collected at breast Tanner stages 2 (B2; n = 256) and B4 (n = 338).

Results

After adjusting for fat percentage at breast density measurement, ER-α methylation at B2, and cellular heterogeneity, we observed an inverse association between B4 average ER-α DNA methylation and BV and FGV. Geometric mean BV was 15% lower (95% CI: − 28%, − 1%) among girls in the highest quartile of B4 ER-α methylation (6.96–23.60%) relative to the lowest (0.78–3.37%). Similarly, FGV was 19% lower (95% CI: − 33%, − 2%) among girls in the highest quartile of B4 ER-α methylation relative to the lowest. The association between ER-α methylation and breast composition was not significantly modified by body fat percentage and was not influenced by pubertal timing.

Conclusions

These findings suggest that the methylation profile of ER-α may modulate adolescent response to estrogen and breast composition, which may influence breast cancer risk in adulthood.

Electronic supplementary material

The online version of this article (10.1186/s13148-018-0553-5) contains supplementary material, which is available to authorized users.

Role of APOE Gene in Bone Mineral Density and Incidence of Bone Fractures in Brazilian Postmenopausal Women

Osteoporosis is one of the major diseases that affects mostly postmenopausal women. Despite being a multifactorial disease, some genes have been shown to play an important role in osteoporosis. Bone mineral density (BMD) is still largely used to diagnose it, although many other biomarkers are used to better follow the disease onset. It has been shown that the apolipoprotein E (APOE) gene could be a biomarker for risk of fractures as well as to predict lower BMD in patients with osteoporosis. The human APOE gene encodes 3 protein isoforms called ApoE2, ApoE3, and ApoE4, resulting in 4 possible genotypes, because they are a product of a single nucleotide polymorphism found in this gene. So far, the APOE4 allele has been associated with low BMD in postmenopausal women and to incidence of bone breaking in older women. This study aimed to investigate the role of ApoE isoforms in a cohort of 413 postmenopausal Brazilian women. These patients were randomly recruited, clinically examined, and subjected to dual-energy X-ray absorptiometry to measure their BMD. Patients were further grouped as normal BMD (T-score < 0.5) or low BMD (T-score > 1.0, osteopenic or osteoporotic). Patients with osteopenia or osteoporosis were further genotyped for APOE alleles as well as tested for many serum bone turnover biomarkers. Our data showed that presence of the APOE3 allele was associated with both higher BMDs and higher serum concentrations of osteocalcin and alkaline phosphatase, biomarkers for bone formation. On the other hand, the APOE2 and APOE4 alleles were associated with lower BMD as well as higher levels of serum C-terminus collagen peptide and urinary deoxipyridinolines, biomarkers for bone resorption. However, these effects on lower BMD and bone resorption biomarkers observed in either APOE2 or APOE4 alleles were eliminated when patients' genotype carried the APOE3 allele. Codominance of the APOE3 allele was also associated with lesser cases of bone fractures in these patients within a 5-year follow-up. In conclusion, our data show that APOE4 may be associated with lower bone formation as well as increased risk of osteoporosis and bone fractures, whereas APOE3 seems to decrease lowering BMD in postmenopausal women, and its presence seemed to lower the incidence of bone breaking in patients with osteoporosis.

The SRGAP2 SNPs, their haplotypes and G × E interactions on serum lipid traits

Maonan nationality is a relatively conservative and isolated minority in China. Little is known about the association of the Slit-Robo Rho GTPase activating protein 2 gene (SRGAP2) single nucleotide polymorphisms (SNPs) and serum lipid levels in the Chinese populations. This study was performed to clarify the association of the SRGAP2 rs2483058 and rs2580520 SNPs and their haplotypes with serum lipid traits in the Maonan and Han populations. Genotyping of the 2 SNPs was performed in 2444 unrelated subjects (Han, 1210 and Maonan, 1234) by polymerase chain reaction and restriction fragment length polymorphism combined with gel electrophoresis, and then confirmed by direct sequencing. The allelic (rs2483058) and genotypic (rs2483058 and rs2580520) frequencies were different between the two ethnic groups. Four haplotypes were identified in our populations, and the rs2483058G-rs2580520C haplotype was the commonest one. The rs2483058C-rs2580520G haplotype was associated with an increased risk of dyslipidemia, and showed consistent association with serum total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), apolipoprotein (Apo) A1 levels, and the ApoA1/ApoB ratio. These results indicated that the SRGAP2 SNPs and their haplotypes were associated with serum lipid levels. Their haplotypes can explain much more serum lipid variation than any single SNP alone, especially for serum TC, HDL-C and ApoA1 levels.