Microbiome

Linking sow ABO genotype to milk glycome and piglets' gut microbiome

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Abstract

We previously showed in a large Chinese heterogeneous stock that an interspecies 3-kb deletion in the ABO genes of Suidae decreases the abundance of the p.75.a5 genus of Erysipelotrichaceae in the gut by decreasing the concentration of free intestinal GalNAc. Bacteria from this genus utilize GalNAc as a carbon source using a constitutively active GalNAc operon (Yang et al., 2022). We herein show that this polymorphism also segregates in Belgian pig populations, with the same effect on p.75.a5 abundance. We genotyped 250 pigs from a [Landrace à— Large White] à— Piétrain cross using an Illumina 50K SNP array and for the "O" deletion at the ABO locus using custom-made PCR assay. We collected individual feces at ~180 days, extracted DNA, amplified the V3-V4 region 16S region and sequenced the corresponding PCR products on an Illumina MiSeq. We conducted microbiota analyses using QIIME2 (Bolyen et al., 2019), DADA2 (Callahan et al., 2016) and the Greengenes 2 database (to which we added p.75.a5 sequences). We analyzed the effect of genotype on bacterial abundance (log-centered ratio) using a linear mixed model including sex and genotype (additive plus dominance effects) as fixed effects, and kinship and pen-sharing as random effects. The "A" allele increased p.75.a5 abundance in a dominant fashion (p = 2.3 à— 10⁻⁷), as expected. We showed that including 22 microbial principal components as fixed effects markedly increased the significance of the "AO" effect (p = 2.2 à— 10⁻¹¹), presumably by correcting the phenotypes for hidden confounders. We also showed that sensitivity is increased by co-estimating the effects of the covariates in the model rather than to work with pre-corrected residuals. We scanned the whole genome using either single SNP markers or a previously described haplotype-based model (Druet & Georges, 2010; Zhang et al., 2012). No other convincing associations were detected with either approach. The N-acetyl-galactosaminyl transferase encoded by ABO locus is strongly expressed in the digestive tract where it is thought to post-translationally modify intestinal mucins. It is also conceivable that it affects the glycome of the mammary gland, thereby affecting GalNAc concentrations in milk. To verify whether sow ABO genotype affects offspring intestinal microbiome composition, DNA and fecal samples were collected at 26 days, 8 and 22 weeks from ~1,000 piglets from 91 [Landrace à— Large White] sows and six Piétrain boars, all genotyped as above. We performed full glycome analysis (MS/MS-based N-glycan profiling and xCGE-LIF glycoprofiling) of milk samples of all sows and 16S rRNA profiling of piglet fecal samples as described above. We are evaluating the effect of ABO locus and the remainder genome of the sow on milk glycome composition and piglet microbiota. Latest results will be presented.

Keywords: 2026

How to Cite:

Hooyberghs, K., Hupperts, C., Dupont, S., Li, Y., Tang, L., Beckers, E., De Kort, J., Patteet, I., Meyermans, R., Janssens, S., Buys, N., Charlier, C. & Georges, M., (2026) “Linking sow ABO genotype to milk glycome and piglets' gut microbiome”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2295660. doi: https://doi.org/10.31274/wcgalp.24355

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