Impact of excess sugar on the whole genome DNA methylation pattern in human sperm.
Study Goal
The researchers aimed to determine whether a high-sugar diet affects DNA methylation in human sperm and to describe the sperm methylome.
Results Summary
The study found modest effects of excess sugar on DNA methylation in sperm, particularly in imprinted genes, highly expressed genes, and genes linked to fertility. Methylation levels varied by genomic region, with 3'UTRs and introns showing the highest methylation and 5'UTRs and CpG islands the lowest.
Population
15 males
Effective Dosage
150% of estimated total energy expenditure from sugar
Duration
2 weeks (1 week standardized diet, 1 week high-sugar diet)
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
diet intervention, including excess sugar | neutral | methylome in human sperm | 15 males | - | affects | #1 |
high-sugar diet providing 150% of their estimated total energy expenditure | neutral | methylation of 143 sites linked to fertility | 15 males | - | associated with | #2 |
high-sugar diet providing 150% of their estimated total energy expenditure | neutral | methylation of 313 sites in imprinted genes | 15 males | - | associated with | #3 |
high-sugar diet providing 150% of their estimated total energy expenditure | neutral | methylation of 42 sites in top 1%-expressed genes | 15 males | - | associated with | #4 |
excess sugar | neutral | methylation on imprinted and highly expressed genes, and genes affecting fertility | human sperm | modest | had modest effects on | #5 |
AIMS, PATIENTS & METHODS: Dietary factors may regulate the epigenome. We aimed to explore whether a diet intervention, including excess sugar, affects the methylome in human sperm, and to describe the sperm methylome. We used Whole Genome Bisulfite Sequencing (WGBS) to analyze DNA methylation in sperm taken at three time points from 15 males during a diet intervention; i) at baseline, ii) after one week on a standardized diet, and iii) after an additional week on a high-sugar diet providing 150% of their estimated total energy expenditure. RESULTS: We identified seven nominal diet-associated differentially methylated regions in sperm (p < 0.05). The diet was nominally associated with methylation of 143 sites linked to fertility (e.g. AHRR, GNAS, and HDAC4), 313 sites in imprinted genes (e.g. GLIS3, PEG10, PEG3, and SNURF), and 42 sites in top 1%-expressed genes (e.g. CHD2) (p < 0.05). In sperm, 3'UTRs and introns had the highest levels of methylation, while 5'UTRs and CpG islands had the lowest levels. Non-expressed genes in human sperm were hypomethylated in exons compared with transcribed genes. CONCLUSIONS: In human sperm, DNA methylation levels were linked to gene expression, and excess sugar had modest effects on methylation on imprinted and highly expressed genes, and genes affecting fertility.