Page 43 - Small Animal Clinical Nutrition 5th Edition

Chapter
4

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Nutrigenomics and

Nutrigenetics:

Nutritional Genomics in

Health and Disease

Samer Al-Murrani
Craig D. Thatcher

Michael S. Hand

“It is from the progeny of this parent cell that we all take our looks; we still
share genes around, and the resemblance of the enzymes of grasses to
those of whales is in fact a family resemblance.”
Lewis Thomas

these technologies are collectively referred to as “nutritional
INTRODUCTION genomics.”

A revolution in nutrition is underway.Through newly available
scientific methods and technologies, dramatic advances in NUTRITIONAL GENOMICS AND
understanding the role of nutrition in health and disease are OTHER “OMICS”
within reach. These new tools include:
1. Complete or partially sequenced genomes of many animal, Because nutritional genomics is a relatively new science, the
plant and microbial species (Bell et al, 2001; Lander et al, following discussion includes a review of relevant, but perhaps
2001; Waterson et al, 2002; Kirkness et al, 2003; Seshadri unfamiliar, terminology. Table 4-1 summarizes definitions and
et al, 2006). other related terms.
2. Ample historical evidence suggests nutrients provide “Genome” refers to the full set of an individual’s genes (i.e.,
potent dietary signals via gene control that influence cellu- its genotype). “Phenotype” refers to the entire physical, bio-
lar metabolism and homeostasis, either positively or nega- chemical and physiologic makeup of an animal as determined
tively (Clarke and Abraham, 1992; Muller and Kirsten, by its genome and the animal’s environment. “Genomics”
2003; Straus, 1994). describes the mapping, sequencing and analysis of all genes
3. Laboratory and computer technologies that allow for the present in the genome of a given species (Mutch et al, 2005).
analysis of the molecular response of entire biologic sys- Numerous genomes are available to the public at http://
tems to nutrients (Muller and Kirsten, 2003). www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=genomeprj. The
This chapter will acquaint readers with the current status of term “genomics” is sometimes used loosely to refer to sequence
emerging nutritional technologies and provide insight about analysis, gene expression analysis and single nucleotide poly-
the future potential of these tools. When applied to nutrition, morphism analysis (the last two are discussed below).