DNA and Genealogy, How Did DNA Research Develop to Encompass Genealogical Work?
DNA studies have developed rapidly to help scientist understand biological systems and disease. Genomics are now being applied to fingerprint criminals and cousins.
The discovery of DNA, the material that provides information for individual human traits, dates to the late nineteenth century. Although early attempts to unravel the secrets of DNA took many years, the last 25 years have seen quick progress and the application of DNA to many fields of research, including genealogical work. Communities are now forming that use DNA results to trace relationships and to test previously held theories about the human condition.
Discovery of DNA
After DNA’s initial discovery, scientists needed to understand more about its structure and how DNA worked. In 1962, James Watson, Francis Crick, and Maurice Wilkins refined the earlier research and won the Nobel Prize.
They had shown that the DNA molecule is made of two chains of nucleotides. Matching base pairs interlocked in the middle of the double helix and each strand of the DNA molecule is the template for the other. During cell division, the two strands separate and another is built that is an exact copy. DNA reproduces itself without change, except for the occasional error or mutation.
The Human Genome Project was launched in 1990 to stimulate the biotechnology industry. Later in the decade, advances were made largely due to advances in computer capacity. DNA research has added to our understanding of the role of genes in sustaining and defining life. It has enhanced our understanding of the human biological system and has been extended to the study of many other living organisms.
Application of Genetics in Other Fields
The differences in DNA that are related to inherited diseases have been studied since 1984. Sir Alec Jeffreys developed a DNA fingerprinting technique that looked for mutations in DNA called stutters, where a sequence of base pairs is repeated several times. This fingerprinting technique has been used to resolve legal disputes over paternity. Other applications of this method were soon developed to identify individuals in criminal investigations.
The sequencing of DNA is a complex process, but advances have made the use of genetics more affordable. New techniques for collecting DNA samples by harvesting cells by swabbing the inside of the cheek have made lead to the rapid advance of genetics in the genealogy arena.
Two Types of DNA
DNA or deoxyribonucleic acid is the sequence of base pair chemicals that define each human being as a unique individual. There are two types of DNA: nuclear DNA, which is found in the nucleus of a cell, and mitochondrial DNA, which is found outside the nucleus of a cell. Nuclear DNA is passed from father to son and is used by genealogist to trace paternal lines. Mitochondrial DNA is passed from mothers to their children. In human reproduction, sperm does not pass its mitochondria to the egg at conception, so mitochondrial DNA can only be examined for information about the mother, her mother, and so forth in the maternal line.
DNA and Genealogy Emerge
Bryan Sykes, a scientist studying inherited disease, applied his knowledge of DNA and study of genealogy to a book that has piqued the interest of many. In The Seven Daughters of Eve he used mitochondrial DNA information to prove that most Western Europeans descend from one of seven women who lived within the last 50,000 years.
Bennett Greenspan approached scientist Mike Hammer with a question about DNA after seeing a program about Hammer’s investigative work using DNA. The two founded Family Tree DNA, the first commercial concern to establish genetic genealogy communities.
Today, groups have formed to connect individuals to others with the same surname to compare DNA and documentation. Families with common names like Smith or Jones can find out if they are a genetic match and move their personal genealogical quest forward. In other cases, such as Bryan Sykes Saxons, Vikings, and Celts: The Genetic Roots of England and Ireland and the Family Tree DNA Early Chesapeake Project, DNA research is used to layer over traditional documentary research and folklore.