Ballot D, Meyer T E, Bothwell T H, Bezwoda W R, Green A, Baynes R D, Joffe M, Jenkins T
S Afr Med J. 1987 May 16;71(10):639-42.
HLA typing for the A and B loci was carried out in conjunction with measurements of iron status on 38 of the first-degree relatives of 8 patients suffering from idiopathic haemochromatosis (IHC). Seven of the 8 probands had the A3 allele, 2 in the homozygous form. Seven had the B7 allele and in 5 it was present with the A3 allele on the same chromosome. Six family members were diagnosed as homozygous for the HLA-linked iron-loading gene on the basis of genotype assessment, while 27 were assessed as being heterozygous. Five of the 6 homozygous subjects had developed significant iron overload. In contrast, disturbances of iron metabolism in the heterozygotes were mild and present in only 33%. Pseudodominant inheritance of IHC was noted in one family, presumably as the result of a homozygous/heterozygous mating. A pilot epidemiological survey was carried out on 222 Afrikaans-speaking men in an attempt to find affected individuals using the serum ferritin concentration as the screening test. One homozygous subject was identified (genotype A3, B7/A3, B7) and further family studies confirmed the presence of the HLA-linked iron-loading gene. These preliminary results suggest a disease frequency of about 4-5/1,000 in the Afrikaner population.
对8例特发性血色素沉着症（IHC）患者的38名一级亲属进行了HLA A和B位点分型，并同时检测了铁状态。8名先证者中有7名携带A3等位基因，其中2名是纯合子形式。7名携带B7等位基因，其中5名在同一条染色体上与A3等位基因同时存在。根据基因型评估，6名家庭成员被诊断为HLA连锁铁负荷基因纯合子，27名被评估为杂合子。6名纯合子受试者中有5名出现了明显的铁过载。相比之下，杂合子的铁代谢紊乱较轻，仅33%出现。在一个家庭中发现了IHC的假显性遗传，推测是由于纯合子/杂合子交配所致。对222名说南非荷兰语的男性进行了一项初步流行病学调查，试图以血清铁蛋白浓度作为筛查试验来寻找受影响个体。鉴定出1名纯合子受试者（基因型A3，B7/A3，B7），进一步的家族研究证实了HLA连锁铁负荷基因的存在。这些初步结果表明，南非白人人群中该病的发病率约为4 - 5/1000。
