Symonette Caitlin J, Adams Paul C
Schulich School of Medicine and Dentistry., University of Western Ontario, London, Ontario.
Can J Gastroenterol. 2011 Jun;25(6):324-6. doi: 10.1155/2011/463810.
Mitochondrial DNA (mtDNA) and Y-DNA analysis have been widely used to predict ancestral origin. Genetic anthropologists predict that human civilizations may have originated in central Africa one to two million years previously. Primary iron overload is not a common diagnosis among indigenous people of northern Africa, but hereditary hemochromatosis is present in approximately one in 200 people in northern Europe. MtDNA analysis has the potential to determine whether contemporary hemochromatosis patients have an ancient ancestral linkage.
DNA was obtained from buccal smears for mtDNA and Y-DNA analysis. Y-DNA analysis included examination of 20 short tandem repeat markers on the Y chromosome. Analysis of mtDNA involved sequencing of the HVR-1 genetic sequence (nucleotides 16001 to 16520) and was compared with the Cambridge Reference Sequence. MtDNA ancestral haplotypes were predicted from the analysis of the HVR-1 sequence.
Twenty-six male C282Y homozygotes were studied. There were 28 polymorphisms present in the HVR-1 sequence of these participants. The most common polymorphism was present at position 16519 in 15 participants and at position 16311 in eight participants. There were 12 different ancestral haplotypes predicted by mtDNA analysis, with the K haplotype being present in five participants. Y-DNA analysis revealed eight different haplotypes, with R1b being found in 11 of the 26 participants.
Analysis of mtDNA and Y-DNA in 26 hemochromatosis patients suggested that they did not all originate from the same ancestral tribe in Africa. These findings were consistent with the theory that the original hemochromatosis mutation occurred after migration of these ancestral people to central Europe, possibly 4000 years previously.
线粒体DNA（mtDNA）和Y染色体DNA分析已被广泛用于预测祖先起源。遗传人类学家预测，人类文明可能在一到两百万年前起源于非洲中部。原发性铁过载在北非原住民中并非常见诊断，但遗传性血色素沉着症在北欧约每200人中就有1例。mtDNA分析有潜力确定当代血色素沉着症患者是否有古老的祖先联系。
从口腔拭子中获取DNA用于mtDNA和Y染色体DNA分析。Y染色体DNA分析包括检测Y染色体上的20个短串联重复序列标记。mtDNA分析涉及对高变区1（HVR-1）基因序列（核苷酸16001至16520）进行测序，并与剑桥参考序列进行比较。通过对HVR-1序列的分析预测mtDNA祖先单倍型。
对26名男性C282Y纯合子进行了研究。这些参与者的HVR-1序列中存在28个多态性。最常见的多态性出现在15名参与者的16519位和8名参与者的16311位。mtDNA分析预测出12种不同的祖先单倍型，其中K单倍型在5名参与者中出现。Y染色体DNA分析揭示了8种不同的单倍型，26名参与者中有11名的单倍型为R1b。
对26名血色素沉着症患者的mtDNA和Y染色体DNA分析表明，他们并非都起源于非洲的同一个祖先部落。这些发现与以下理论一致：最初的血色素沉着症突变发生在这些祖先迁移到中欧之后，可能是在4000年前。
