Vitamin D heritability and effect of pregnancy status in Vervet monkeys (Chlorocebus aethiops sabaeus) under conditions of modest and high dietary supplementation. Issue 4 (28th December 2015) - Chittoor, Geetha
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. 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 8 months, which provided a human equivalent of approximately 4, 000 IU/day of vitamin D. All statistical analyses were 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 ( h 2 =0.66, P =0.0004) and TAD ( h 2 =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. Am J Phys Anthropol 159:639–645, 2016. © 2015 Wiley Periodicals, Inc.