Genomics of Reproductive Traits and Cardiometabolic Disease Risk in African American Women

Genetic determinants of age at menarche: does the LIN28B gene play a role? A narrative review

Menarche, the first menstrual period marking the onset of female reproduction, is a milestone of female puberty. The timing of menarche determines the timing of later phases of pubertal maturation in girls and has major implications for health later in life, including behavioral and psychosocial disorders during adolescence and fertility problems and increased risk for certain diseases in adulthood. Over the last few decades, a continuous decline in age at menarche has been noted, with environmental factors contributing to this change in the timing of menarche. However, a genetic component of age at menarche and pubertal onset has been strongly suggested by studies in families and twins wherein up to approximately 80% of the variance in puberty onset can be explained by heritability. Gene association studies have revealed several genetic loci involved in age at menarche, among which LIN28B has emerged as a key regulator of female growth and puberty. LIN28B, a human homolog of Lin28 of C. elegans, is a known RNA-binding protein that regulates let-7 microRNA biogenesis. Genome-wide association studies have identified the association of polymorphisms in the LIN28B gene with age at menarche in several population cohorts worldwide. In this paper, we review the genetic factors contributing to age of menarche, with particular focus on the identified polymorphisms in LIN28B gene.

Shared Genetics between Age at Menarche and Type 2 Diabetes Mellitus: Genome-Wide Genetic Correlation Study

Background: Age at menarche (AAM) has been associated with type 2 diabetes mellitus (T2DM). However, little is known about their shared heritability. Methods: Our data comes from the Taiwan Biobank. Genome-wide association studies (GWASs) were conducted to identify single-nucleotide polymorphisms (SNPs) related to AAM-, T2DM-, and T2DM-related phenotypes, such as body fat percentage (BFP), fasting blood glucose (FBG), and hemoglobin A1C (HbA1C). Further, the conditional false discovery rate (cFDR) method was applied to examine the shared genetic signals. Results: Conditioning on AAM, Quantile-quantile plots showed an earlier departure from the diagonal line among SNPs associated with BFP and FBG, indicating pleiotropic enrichments among AAM and these traits. Further, the cFDR analysis found 39 independent pleiotropic loci that may underlie the AAM-T2DM association. Among them, FN3KRP rs1046896 (cFDR = 6.84 × 10-49), CDKAL1 rs2206734 (cFDR = 6.48 × 10-10), B3GNTL1 rs58431774 (cFDR = 2.95 × 10-10), G6PC2 rs1402837 (cFDR = 1.82 × 10-8), and KCNQ1 rs60808706 (cFDR = 9.49 × 10-8) were highlighted for their significant genetic enrichment. The protein-protein interaction analysis revealed a significantly enriched network among novel discovered genes that were mostly found to be involved in the insulin and glucagon signaling pathways. Conclusions: Our study highlights potential pleiotropic effects across AAM and T2DM. This may shed light on identifying the genetic causes of T2DM.

A roadmap for social determinants of health and biological nursing research in the National Institute of Nursing Research 2022-2026 Strategic Plan: Optimizing health and advancing health equity using antiracist framing

BACKGROUND

Health equity is essential for improving the well-being of all individuals and groups, and research remains a critical element for understanding barriers to health equity. While considering how to best support research that acknowledges current health challenges, it is crucial to understand the role of social justice frameworks within health equity research and the contributions of minoritized researchers. Additionally, there should be an increased understanding of the influence of social determinants of health on biological mechanisms.

PURPOSE

Biological health equity research seeks to understand and address health disparities among historically excluded populations.

DISCUSSION

While there are examples of studies in this area led by minoritized researchers, some individuals and groups remain understudied due to underfunding. Research within minoritized populations must be prioritized to authentically achieve health equity. Furthermore, there should be increased funding from National Institutes of Health to support minoritized researchers working in this area.

Apolipoprotein E Gene Polymorphism Effects on Lipid Metabolism and Risk of Cerebral Infarction in Northwest Han Chinese Population

Background

The apolipoprotein E (ApoE) genetic variation may contribute to the development of Cerebral Infarction (CI). Serum lipid levels are known risk factors for CI, but the effect of the ApoE gene polymorphism on lipid metabolism remains unclear. This retrospective cohort study was designed to determine the role of ApoE genotypes in CI risk and the relationships between ApoE gene polymorphism and serum lipid levels among the population of northwest China.

Patients and Methods

517 CI patients and 517 non-CI controls were enrolled in the study. Polymerase chain reaction and hybridization were utilized to determine the ApoE gene polymorphisms.

Results

The ε3/ε4 genotype and ε4 allele frequency were significantly higher in CI patients than in controls. When stratified by age and sex, statistically significant differences in the distribution and frequency of the ε3/ε4 genotype and ε4 allele were found between patients and controls. Compared to ε2 carriers, ε4 carriers had significantly lower ApoE levels and higher low-density lipoprotein cholesterol (LDL-C), ApoB and ApoB/ApoA-I levels in both two groups. Additionally, control participants with ε4 carriers had significantly higher levels of lipoprotein and total cholesterol (TC) levels than ε2 carriers, while CI patients with ε4 carriers had a significantly lower level of ApoA-I. After adjusting for other established risk factors, drinking, hypertension, lipoprotein, triglycerides (TG) and ε4 allele were significant independent risk factors for CI, which was shown to be associated with a nearly two-fold CI risk.

Conclusion

This study demonstrated that ε4 allele is independent risk factors for CI among patients in Northwest China. ApoE polymorphism was associated with CI, which was partly mediated through blood lipids and may also be mediated through non-lipid pathways. These data might be of great clinical significance in individualized preventive and therapeutic strategies.

African American Women's Perceptions of Cardiovascular Disease After Myocardial Infarction: A Phenomenological Inquiry

BACKGROUND

The primary cause of death among African American women older than 50 years is cardiovascular disease. Cardiovascular disease affects more than 16.8 million Americans and occurs when plaque builds up in the arteries that provide blood to the heart. This often leads to a partial or complete blockage, causing a myocardial infarction (heart attack). There is limited research regarding the lived experiences of African American women before and after a myocardial infarction.

OBJECTIVE

The purpose of this qualitative study was to explore the experiences of African American women living in the southern region of the United States who have experienced a myocardial infarction.

METHODS

A hermeneutic phenomenological framework guided the study. Semistructured, audiotaped interviews were conducted to elicit narratives from 7 participants. Interview data were transcribed verbatim and then coded and analyzed using Colaizzi's phenomenological analysis framework.

RESULTS

The findings revealed 6 major themes: life before myocardial infarction, causes of my myocardial infarction, myocardial infarction warning signs, life after myocardial infarction, cardiac rehabilitation, and family support. Lifestyle changes must be implemented to prevent a second blockage. Attending cardiac rehabilitation and incorporating regular physical exercise are recommended to help prevent further heart damage and to improve quality of life.