Pattern of Inheritance

The inheritance patterns observed will depend on whether the allele is found on an autosomal chromosome or a sex chromosome, and on whether the allele is dominant or recessive. Genetic traits in humans can be tracked through family pedigrees. Many inherited disorders in humans are controlled by a single gene. A single gene may affect many phenotypic characters.e.g. Pleiotropy occurs when one gene influences many characteristics. Sickle-cell disease is a human example of pleiotropy. Ancestry testing is a form of direct-to-consumer genetic testing designed to inform customers about their genetic ancestry. There are generally three types of ancestry testing: Y chromosome testing, mitochondrial DNA testing, and autosomal DNA testing.

Y-DNA tests

Because y-chromosomes are passed from father to son virtually unchanged, males can trace their patrilineal (male-line) ancestry by testing their y-chromosome. Since women don’t have y-chromosomes, they can’t take y-DNA tests.

mtDNA tests

Mitochondrial DNA tests trace people’s matrilineal (mother-line) ancestry through their mitochondria, which are passed from mothers to their children.Since everyone has mitochondria, both males and females can take mtDNA tests. Mitochondrial DNA testing uncovers a one’s mtDNA haplogroup, the ancient group of people from whom one’s matrilineage descends. Because mitochondria is passed on only by women, no men (nor their ancestors) from whom one descends are encapsulated in the results.

Autosomal DNA tests

Autosomal DNA tests trace a person’s autosomal chromosomes, which contain the segments of DNA the person shares with everyone to whom they’re related (maternally and paternally, both directly and indirectly). Autosomal DNA tests can confirm ethnicity percentages and close relationships with a high level of accuracy.

For more information about ancestary test see the link below:

https://support.ancestry.com/s/article/Y-DNA-mtDNA-and-Autosomal-DNA-Tests