Genealogical DNA testing myths
From ISOGG Wiki
This article attempts to dispel some of the genealogical DNA testing myths.
Myth #1: Do we need to dig up our ancestors to get their DNA?
No! Their DNA is contained within your DNA, to some extent. For males, the Y-chromosome is passed from father to son on down through the generations. Males and females also receive mitochondrial DNA (mtDNA) from their mothers, which also contains the DNA of their direct maternal line. However, only females will pass mtDNA on to their children.
Myth #2: Is the DNA collected by a blood test?
No. Commercial DNA testing companies utilize saliva/buccal cell sampling via swabs and various other collection containers.
Myth #3: Can an insurance company or employer use my DNA test against me for insurance or employment purposes?
The U.S. recently passed legislation known as the Genetic Information and Non-Discrimination Act (GINA) to protect citizens from genetic information being used against them for insurance or employment purposes. The U.K. has already passed similar legislation - the Human Tissue and Privacy Act of 2004.
Myth #4: Do my DNA results reveal any medical conditions?
The section of the Y-chromosome used for genealogical DNA testing is non-coding DNA, in that it does not recombine (mix) or have any known uses other than to fill the spaces in between your genes. However, because this DNA does not mix, and it changes very slowly (mutates) it's beneficial for use in genealogical applications.
With mitochondrial DNA testing, the low-resolution HVR1 and HVR2 tests sequence a portion of the mtDNA genome known as the "Hypervariable Region" (HVR) which, like the Y-chromosome DNA, does not mix and it changes very slowly. Both HVR1 and HVR2 tests which are used for genealogical and deep ancestry purposes, do not reveal any medical conditions. However, a full mitochondrial sequence test may reveal medical conditions, but this information is not analyzed by your testing facility. You would need to seek further analysis from a specialist (for example, the custom mtDNA reports from Dr Ann Turner). The full sequence test results are not public information, nor made available to your DNA Project Administrator.
The autosomal DNA test from 23andMe includes health and trait reports. Autosomal DNA tests for genealogical purposes are also offered by Ancestry DNA and Family Tree DNA (the Family Finder test), but neither company provides any medical information. However, it is sometimes possible to extract some health and trait information by analyzing the data with one of the autosomal DNA tools such as Promethease.