Biomedical subjects

Xiangyang Lou

Publications and source records attributed to Xiangyang Lou.

3 recordsLinked to original sources

PubMed2026

DNA methylation signatures in skeletal muscle associated with physical function in healthy older adults.

Despite the substantial variability in physical function among older adults, the molecular mechanisms remain poorly characterized, particularly within skeletal muscle. This study aimed to determine the patterns of DNA methylation in skeletal muscle associated with physical function in healthy older adults. We analyzed DNA methylation (EPIC v2 array; 875,554 CpG sites) in skeletal muscle from 92 healthy older adults (median age 74; 62% female). Associations were examined across five phenotypes: Short Physical Performance Battery (SPPB), 6-min walk test (6MWT), handgrip strength, perceived disability (PAT-D), and lifestyle health (modified Life's Essential 8). Linear regression models adjusted for age, sex, race, BMI, and muscle fiber composition. Genomic inflation corrected via the BACON method (FDR < 0.05). Gene set enrichment analysis was performed on suggestive hits (FDR < 0.1). We identified significant differentially methylated probes (DMPs) and regions (DMRs) across all phenotypes: SPPB (70 DMPs, 22 DMRs), 6MWT (16 DMPs, 566 DMRs), handgrip strength (2 DMRs), PAT-D (19 DMPs, 1 DMR), and lifestyle health (2 DMPs). DMRs largely overlapped promoters. Identified genes overlapped known musculoskeletal and neurological GWAS hits, including RUNX2 and FOXL1 (bone mineral density), IGFBP3 (muscle mass), and NEK1 and SHANK1 (neurological function). Enrichment analysis revealed that 6MWT-associated genes relate to nervous and skeletal system development, while handgrip-associated genes involve cytoskeletal dynamics and protein assembly. Epigenetic variation in aging skeletal muscle is associated with physical function. The enrichment of pathways related to nervous and musculoskeletal development suggests specific epigenetic mechanisms underlying functional decline, offering potential targets for intervention in older adults.

DNA methylation↗

PubMed2005

Genetic control of the opaque-2 gene and background polygenes over some kernel traits in maize (Zea mays L.).

Some kernel traits of agronomical importance in maize are affected by the opaque-2 (o2) gene and background polygenes, which express in different genetic systems such as embryo, endosperm, cytoplasm and maternal plant. A genetic model for seed quantitative traits with the o2 gene effects and polygenic effects as well as their GE interactions was used for protein content, lysine content, oil content and kernel density in maize. The results suggested that the o2 gene was involved in the traits investigated but the effects of the o2 gene were distinctive on various traits. The effects of the o2 gene were large on lysine content and protein content while minor on oil content. There was a substantially wide quantitative variation from polygenes expressing in different genetic systems for the traits evaluated. Significant GE interactions of the o2 gene and background polygenes declared that not only the main effects but also specific expressions depending on environments were responsible for variation of the traits studied. There seemed to have strong maternal heterosis and slight embryo heterosis for kernel density.

DNA-Binding Proteins↗

PubMed2003

A method for marker-assisted selection based on QTLs with epistatic effects.

A method for marker-assisted selection (MAS) based on quantitative trait loci (QTLs) with epistatic effects is proposed. The efficiency of such method is investigated by simulations under a wide range of situations. In the presence of epistasis, MAS generally yields longer persistence response than that based exclusively on additive or additive and dominance. Neglecting epistasis could result in considerable loss in response, and more pronounced at later generations. In addition to population size and trait heritability, genetic variance configurations play an important role in determining both the short- and long-term efficiencies of MAS. MAS using breeding values not only achieves higher response, but also tends to have smaller standard error than other methods in most cases. Errors in QTL detection cause distinct reductions in responses to MAS in most cases. It is thus concluded that verifications of putative QTL and its magnitude of effect and accurate map chromosome location are imperative to realize the potentials of MAS.

Epistasis, Genetic↗