What is the difference between a genetic marker and a gene? How will this information be used to help in genealogical research?
A gene is a segment of DNA responsible for a protein or other biological molecule. These proteins and molecules will have structural or physiological properties that contribute to the biologic function of an individual. Alteration in the DNA sequence of a gene may cause a protein to be incorrectly manufactured and result in a disease condition. Segments of DNA between genes have been termed “spacer” or “junk” DNA because most have no known function. It is estimated that the majority of the human genome consists of this junk DNA. Alterations or mutations in “junk” DNA will have no physical effect on the individual. Genetic markers are specific locations on the chromosome where there is known variability. This variability can be used to identify closely related individuals. Since genetic markers are not responsible for disease conditions we have focused our efforts on using this system to help in genealogical reconstruction.
