(OR19-04-26) Genetic Ancestry Predictors of Calcium Absorption and Metabolism in Healthy Young Adults

Monday, July 27, 2026

11:06 AM - 11:18 AM ET

Location: National Harbor 4-5

Presenting Author(s)

Marta Vuckovic, PhD (she/her/hers)

Research Scientist
San Diego State University
San Diego, California, United States

Disclosure(s): No relevant financial relationship(s) with ineligible companies to disclose.

Co-Author(s)

SC

Sisi Cao

San Diego State University, United States
Christina N. Vialva, B.A. (she/her/hers)

Research Assistant
San Diego State University
Chula Vista, California, United States
ZJ

Zhongli Jiang

University of California, Irvine, United States
KK

Karisa Ke

University of California, Irvine, United States
CG

Charles Ginsberg

University of California, San Diego, United States
AH

Andrew Hoofnagle

University of Washington, United States
MZ

Min Zhang

University of California, Irvine, United States
Shirin Hooshmand, PhD, RD

Professor
San Diego State University
San Diego, California, United States
Mark Kern, PhD, RD

Professor of Exercise and Nutritional Sciences
San Diego State University
San Diego, California, United States
GW

Gina Woods

University of California, San Diego, United States
CW

Connie Weaver

San Diego State University, United States

Disclosure(s):

Marta Vuckovic, PhD: No relevant financial relationship(s) with ineligible companies to disclose.

Christina N. Vialva, Bachelors of Arts Chemistry: No relevant financial relationship(s) with ineligible companies to disclose.

Shirin Hooshmand, PhD, RD: No relevant financial relationship(s) with ineligible companies to disclose.

Mark Kern, PhD, RD: No relevant financial relationship(s) with ineligible companies to disclose.

Objectives: Racial differences in gut calcium absorption are not well understood. The purpose of this randomized control trial study was to investigate the relationship between single nucleotide genetic polymorphisms (SNPs) associated with genetic ancestry and fractional calcium absorption (FCA) in a cohort of young healthy adults from four self-reported racial backgrounds: Asian, Black, Hispanic/Latino and White.

Methods: Sixty-six young healthy adults (n=32 female) from the San Diego, CA area were recruited for the study. FCA analysis was determined using the dual stable calcium isotope tracer method following a 48 h-controlled diet and was log-transformed prior to genetic association analysis to improve normality. Whole genome sequencing was conducted on baseline serum samples using the PacBio long-read platform. Variant calling followed the GATK Best Practices workflow, ancestry proportions were identified using ADMIXTURE, and gene-level associations were evaluated with MAGMA.

Results: FCA was 21 ± 15% lower among the Black participants compared to other racial groups (p < 0.05). Genes that are known to be directly involved in calcium absorption and metabolism (TRVP5/6, ATP2B1, VDR) showed no significant association with observed differences in FCA among the racial groups. Serum 25-hydroxy vitamin D levels did not differ significantly among the groups (p > 0.05). Instead, SNPs in genes involved in hematopoiesis, immune function (PTX4), steroid metabolism (SULT2A1), osteoblast differentiation / maturity and inflammation (SPATS2L) were significantly correlated with observed differences in calcium FCA (FDR < 0.001).

Conclusions: Genetic predictors of calcium absorption and metabolism are complex and involve genes that are not known to be directly involved in calcium transport and cellular binding.

Funding Sources: National Dairy Council