# Genome-Wide Association Study of Genetic Variants Associated with Serum Albumin Levels in Chinese Winter Sports Athletes

## TL;DR

This study finds genetic variants linked to blood albumin levels in Chinese winter athletes, which could help personalize training and health monitoring.

## Contribution

The study identifies genetic variants associated with albumin levels in a specific athlete population and explores their biological mechanisms.

## Key findings

- 113 SNPs were found to be associated with serum albumin levels in Chinese winter sports athletes.
- Nine candidate SNPs explained 51.1% of the variance in albumin levels in the study sample.
- Functional analysis linked the variants to tissues like the liver and kidney and to metabolism-related pathways.

## Abstract

Blood albumin is an important protein that reflects nutrition, metabolism, and recovery status in athletes and is widely used in training monitoring. However, albumin levels can vary greatly between individuals, and the reasons for these differences are not fully understood. This study investigated whether genetic differences contribute to variation in blood albumin levels in Chinese winter sports athletes. We analyzed blood samples and genetic data from athletes preparing for the Winter Olympic Games. Albumin levels showed clear individual differences but did not differ between higher- and lower-level athletes. We identified multiple genetic variants that were associated with albumin levels, with several key variants explaining a large proportion of the individual differences. Further analysis suggested that these genetic variants may influence albumin levels through organs such as the liver and kidneys and through pathways related to protein and hormone metabolism. These findings improve our understanding of why athletes respond differently to training and recovery and suggest that genetic information may help interpret blood test results more accurately. This work may contribute to more individualized training monitoring and health management strategies for athletes.

This study aimed to explore genetic variants associated with serum albumin (ALB) levels in Chinese winter sports athletes using genome-wide association analysis (GWAS) and to investigate potential regulatory mechanisms using bioinformatics annotation. A total of 382 Chinese winter sports athletes were recruited. ALB levels were compared between elite and non-elite athletes. GWAS was conducted using PLINK v1.9, with ALB as the phenotype and sex, age, and principal components as covariates. Associated SNPs were annotated using GTEx and SNPnexus. No significant differences were observed in ALB levels between elite and non-elite male or female athletes, and ALB levels in all groups followed a normal distribution. We identified 113 SNPs reaching a suggestive significance threshold (p < 1 × 10−5), with per-variant variance explained estimates (7.11–11.76%) reflecting model fit within this cohort. A stepwise regression model highlighted nine candidate SNPs that together explained 51.1% of ALB variance in the study sample. Functional annotation suggested that several variants show eQTL or sQTL signals in tissues relevant to ALB biology (e.g., liver and kidney), and pathway enrichment analyses implicated amino acid and hormone metabolism. Overall, these findings are hypothesis-generating; independent replication in additional and ancestry-matched cohorts (and follow-up functional studies) is required to confirm the robustness of the associations and clarify causal mechanisms.