Determining variation of calcitonin receptor genotypes in commercial pigs A. R. McGee, L. Alexander, C. H. Stahl Department of Animal Science, Iowa State University Introduction

Due to physiological and genetic similarities between pigs and humans, pigs serve as great models for the study of nutritional and genetic factors that affect bone metabolism. Clinical signs of phosphorus deficiency in pigs and humans parallel in that both result in poor bone integrity (Glass et al., 2006). Recent studies have shown increases in the expression of

CALCR

in phosphorus deficient pigs which suggests that genetic background influences metabolic responses to dietary phosphorus deficiency (Hittmeier et al., 2006). Recognition of these changes in gene expression may aid in understanding the regulation of phosphorus metabolism between differing pig genetic lines. The objective of this study was to determine the frequency of polymorphisms in

CALCR

within a sample population for development of potential strategies to utilize these genotypes.

Materials and Methods

Animals and DNA Extraction

: • 78 females piglets from a commercial synthetic white line • 25 mg of tissue from clipped tails used for DNA extraction • DNA extracted using Qiagen DNeasy Tissue Kit (250) ( Valencia, CA)

PCR :

• 60 ng of purified DNA used • PCR conditions →Denatured at 94˚C for 5 min.

→30 cycles: 94˚C for 30 sec.

55˚ C for 30 sec 72˚C for 40 sec.

→Extended at 72ºC for additional 7 min.

→Cooled to 4ºC • Product run on 1.5 % agarose gel

Digestion:

• Digestion reaction with Ban II restriction enzyme • Reaction incubated at 37ºC for 4 hrs.

• Digestion product run on 3 % agarose gel

Ban II PCR-RFLP

11 12 22

CALCR Genotype Frequency

30 20 10 0 60 50 40 22 12

Genotypes

11

Results

•The 22 genotype had the greatest frequency at 48.7 %.

•The 12 genotype made up 35.9%.

•The 11 genotype appeared the least at 14.1%.

478 bp 332 bp 145 bp Discussion

Identifying the frequencies of

CALCR

genotypes will aid in further exploration of genetic influences on animal and human health. By understanding the interaction between genetics and nutrition, we hope to determine genotype-specific dietary requirements as well as develop strategies for more efficient phosphorus utilization in commercial pig production based on such requirements. Recognition of these genotypes within human populations may also lead to the formation of tests for early detection of low bone density, which can result in diseases such as osteoporosis.

Acknowledgements

This work was funded in part by the Biotechnology Research and Development Corporation (BRDC), the IAHEES and the Center for Integrative Animal Genomics at ISU.