More and more adoptees are turning to a DNA test to help them uncover their birth ancestry during an adoption search. Some turn to DNA testing to verify a birth family connection; this was the case with Olympic skier Toby Dawson's adoption search. Before you use a DNA test, first learn some basics.
Know a Gene from a ChromosomePhysical traits and characteristics are determined from our genes. A genome is a complete set of 30,000 to 40,000 genes. A chromosome holds our genetic material. Chromosomes carry the genetic information in long strands of DNA called genes. The DNA is a blue print for creating a human. Each person has 22 numbered pairs of chromosomes and a single pair of sex chromosomes. Each pair of chromosomes is made up of one chromosome that was inherited from the father and one from the mother.
Looking for MutantsSo because we get half of our chromosomes from our fathers and half from our mothers, each half represents our ancestors and what has been passed down to us through the maternal and paternal line. The issue is that this information has been shuffled. Only parts of our genome remains unshuffled from parent to child. There is only small segments of our genetic code that is occasionally mutated. The mutations then become markers of our descent.
The Y-LineAll chromosomes are found in matching pairs except for the Y chromosome, or sex chromosome. This chromosome comes from the father. Because the Y chromosome doesn't have a match it escapes from the shuffling that occurs with each new generation. This means that the Y is allowed to pass down through the male line of descendants changed only by some random mutational events.
The mtDNAThe mtDNA or Mitochondrial DNA is passed from a mother to her offspring, both male and female. The mtDNA that is within you is the same that is within your mother and her mother, but only females continue to pass on that same mtDNA to her offspring. This DNA can be quickly scanned to see the many mutational events that have been passed down through the maternal line.
How the DNA Test Is DoneA simple cotton swab is swiped along the inside of a person's cheek. This is very easy and painless; so simple that a newborn can have it done. This swab sloughs off skin cells from the inside of the cheek. These cells contain the genes or DNA. The swab is then sent to a DNA lab for analysis and compared to other family member's DNA.
Know Your GoalWhat is your goal with a DNA test?
- Do you want to be added to an adoption reunion registry in order to find birth relatives?
- Do you want to confirm the relationship of an already found relative?
- Do you want to discover if your internationally adopted child has a sibling here in the States?
- Do you want to know your deep ancestral history such as through the project being done by The National Geographic?