Kincaid DNA Roots
By Susan Liedtke
Kincaids are like a thicket of trees with branches so interwoven that it is hard to determine to which trunk a limb is attached. Science can help untangle the branches. With more than 130 members from North America, the British Isles, Australia and Holland, the Kincaid DNA Project has identified five distinct trees with more than one member and over a dozen seedlings waiting for growth. Since the majority of participants are from the U.S. or Canada, a certain bias may have helped the largest family in the project obtain dominance. As additional Kincaids are tested the picture will become clearer. Over half the present participants can be placed in 1 of 6 identifiable subfamilies descended from a single ancient unknown male. About 20% of participants descend from another unrelated unknown male. In some localities, genetically unrelated Kincaids lived side by side. The only way to tell from which tree they branch is through a Y-DNA test. The test is easy: a simple swab on the inside of the cheek can link a male Kincaid to his DNA roots.
The science behind the Y-DNA test is a little more complicated. Every human cell carries in it a book of instructions for building and maintaining the individual to which it belongs. This book has 23 chapters consisting of paired DNA (Deoxyribonucleic Acid) strands called chromosomes. An individual inherits one of the paired chromosomes from his mother and one from his father. In 22 of the pairs (all 23 in females) instructions for the same function are found in the same place along each of the paired chromosomes. If the instructions for a given trait are different, one set will dominate or the instructions will blend (such as giving a green eyed baby to brown and blue eyed parents). The 23rd pair of chromosomes in a male do not match each other. He inherits an X chromosome from his mother and a shorter Y chromosome from his father. Usually, it is identical to the Y chromosome that the father inherited from his father. Because a surname is likewise passed down, the Y chromosome is ideal for genealogy.
Each chromosome has paragraphs called genes. The sentences in the paragraph give instructions for making a protein. The words in the sentences name an amino acid or say "start" or "stop". There are only 4 letters in the alphabet. Over the millennia, as chromosomes have been replicated to be passed down to the next generation, words that have no meaning have formed and have not been edited out. These are called "junk DNA". The junk DNA is what is used in genealogical testing. Sometimes in replication a spelling error (mutation) occurs. A sequence of letters may be dropped or repeated. If this mutation is in a true word, the consequences can be disastrous. If it is in junk DNA, then it is passed down harmlessly to the next generation. Family Tree DNA, the testing service used by the Kincaid project, has identified 110 spots on the Y chromosome where the junk DNA mutates at a rate that is useful for genealogy. The lab counts the number of repetitions at those spots. By comparing results from individual tests, patterns emerge that allow predictions of when and if two individuals may have had a common male ancestor.
A chart is maintained with every Kincaid DNA project member's results, grouped by mutations to show those who are most closely related. The chart also shows the earliest Kincaid ancestor known to each participant. This chart and additional information about the project can be found at the Kincaid DNA Project website www.kincaiddna.org.
The Kincaid surname RootsWeb e-mail list is the sponsor of the DNA project. The list is devoted to discussion of Kincaid roots. Instructions on joining the list and access to the list archives may be found on the previous page.