Call to learn more

1-800-514-5208

| Glossary |

Testing Options

Helpful Links

Glossary of Terms

Allele

Alternate sequences for a particular position in the genome. For example, a common variation in the genome is for some populations to have Cytosine (C) in a specific location on their DNA, while other populations would have Thymidine (T).

Biogeographical Ancestry

An estimation of your ancestral proportions based on the evolutionary and geographical history of the human race.

Chromosome

The physical units of heredity: long linear strands of DNA. Humans have 22 autosomal chromosome pairs, plus two sex chromosomes, X and Y. Men have two copies of each autosome, 1, 2, …, 22, X, Y. Women have two copies of each chromosome 1, 2, 3, …, 22, X, X. Each person thus has a total of 46 chromosomes.

Genomics

The study of the complete complement of genetic material in a species.

Genome

All of the genetic material in a species. The human genome is approximately 3,300,000,000 base pairs in length.

Locus (pl. loci)

The name for a physical position on the genome. Can either refer to a large region such as a complete gene or a very specific region, like a particular base pair position.

Maximum Likelihood Estimate (MLE)

The most statistically probable estimate of your ancestral proportions.

Polymorphism

The property of having more than one state or alternate sequence at a particular position. The alternate states are called alleles.

Single Nucleotide Polymorphism (SNP; pronounced snip)

A precise base pair position where different people are found to vary in sequence. Generally two alternate alleles are found at a particular SNP. At least 2,000,000 SNPs are now known and there may be over 30,000,000 in the human genome.