Vitamin D heritability and effect of pregnancy status in Vervet monkeys (Chlorocebus aethiops sabaeus) under conditions of modest and high dietary supplementation

Abstract

Objectives The two objectives of the current study were to: 1) investigate the genetic contributions to variations in serum vitamin D concentrations under two dietary conditions (a standard monkey biscuit diet vs. a diet designed to model typical American consumption) and; 2) explore the interaction of vitamin D with pregnancy status using a cohort of pedigreed female vervet/African green monkeys. Materials and Methods This study includes 185 female (≥3.5 years) vervet/African green monkeys (Chlorocebus aethiops sabaeus) from a multi-generational, pedigreed breeding colony. The 25(OH)D3 concentrations were first measured seven to eight weeks after consuming a “typical American” diet (TAD), deriving 37%, 18%, and 45% of calories from fat, protein sources, and carbohydrates, and supplemented with vitamin D to a human equivalent of 1,000 IU/day. Vitamin D concentrations were assessed again when animals were switched to a low-fat, standard biscuit diet (LabDiet 5038) for eight months, which provided a human equivalent of approximately 4,000 IU/day of vitamin D. All statistical analyses implemented in SOLAR. Results Pregnancy was associated with reduced 25(OH)D3 concentrations. Heritability analyses indicated a significant genetic contribution to 25(OH)D3 concentrations in the same monkeys consuming the biscuit diet (h2=0.66, p=0.0004) and TAD (h2=0.67, p=0.0078) diets, with higher 25(OH)D3 concentrations in animals consuming the biscuit diet. Additionally, there was a significant genotype-by-pregnancy status interaction on 25(OH)D3 concentrations (p<0.05) only among animals consuming the TAD diet. Discussion These results support the existence of a genetic contribution to differences in serum 25(OH)D3 concentrations by pregnancy status and emphasize the role of diet (including vitamin D supplementation) in modifying genetic signals as well as vitamin D concentrations.

Comparison of vitamin D metabolites in wild and captive baboons

“…Additionally, it is likely that genetic factors may attribute to differences in vitamin D within a population. For instance, in vervet monkeys (Chlorocebus aethiops) 66 percent of their 25(OH)D level differences are due to inheritability (Chittoor et al, 2016). In human research, a genetic loci has been identified as associated with differences in 25 (OH)D 3 levels and has an heritability of 7.5% (Jiang et al, 2018).…”