Deconstructing Jaco: Genetic Heritage of an Afrikaner

Abstract

SummaryIt is often assumed that Afrikaners stem from a small number of Dutch immigrants. As a result they should be genetically homogeneous, show founder effects and be rather inbred. By disentangling my own South African pedigree, that is on average 12 generations deep, I try to quantify the genetic heritage of an Afrikaner. As much as 6% of my genes have been contributed by slaves from Africa, Madagascar and India, and a woman from China. This figure compares well to other genetic and genealogical estimates. Seventy three percent of my lineages coalesce into common founders, and I am related in excess of 10 times to 20 founder ancestors (30 times to Willem Schalk van der Merwe). Significant founder effects are thus possible. The overrepresentation of certain founder ancestors is in part explained by the fact that they had more children. This is remarkable given that they lived more than 300 years (or 12 generations) ago. DECONSTRUCT, a new program for pedigree analysis, identified 125 common ancestors in my pedigree. However, these common ancestors are so distant from myself, paths of between 16 and 25 steps in length, that my inbreeding coefficient is not unusually high (f ≈ 0.0019).

Population differences in the postcrania of modern South Africans and the implications for ancestry estimation

“…During the 17 th century the establishment of the Cape colony along the trade route of the Dutch East India Company saw the influx of European settlers into South Africa. The colonists predominantly consisted of Dutch settlers, with later additions of British, French and German immigrants [12,13]. In South Africa the term "coloured" refers to a self-identified social group that exhibits highly diverse origins [14].…”

Appel Botha Cornelitz: The abc of a three hundred year old divorce case

“…The haplotypes were entered on YHRD website [12] to gauge how common these haplotypes are among European men. It is tempting to use South African frequency samples but this would be misleading as a founder effect occurred at the Cape [10] and the current haplotype frequencies would be very misleading. European haplotype frequencies would be a more accurate reflection of haplotype frequencies circulating at the Cape in the late 1600's.…”

“…Of course, this will only be true if adulterous relationships in later generations did not result in a mismatch of haplotypes. Fortunately, the Afrikaner population has an extremely low non-paternity rate of 0.8% [11] which means that direct male descendants will have a high probability of sharing the same Y-chromosome haplotype, even 10 generations later (92% chance = (1-0.008) 10 ).…”

Cancer prevalence in 129 breast-ovarian cancer families tested for BRCA1 and BRCA2 mutations

“…We assembled a total of 129 (127 Caucasian and 2 nonCaucasian) families: 81/129 (62.8%) were Afrikaners, mainly descended from Dutch, German and French immigrants to the South African Cape during the early 17th century, 14 Ashkenazi Jewish families represented 15.5 % (20/129), 12.4% (16/129) were of British/UK origin, and 2.32% (3/129) were of Dutch descent. In addition, there were single families of AfrikanerLebanese, Austrian, Belgian, German, German-British, Polish and Portuguese descent.…”