Blood-group frequencies in south-western England and North Wales: a study in racial variation, together with a search for evidence that the blood-groups possess selective value
Roberts, John Alexander Fraser
1. The material analysed in this thesis consists of records of 120,874 blood donors drawn from the six south-western counties of England, together with a sample of 2,550 donors from three north Welsh counties. • 2. The percentage frequencies of the blood-groups in the west country are: 0 = 44.5, A = 44.0, B = 8.4, AB = 3.2. The corresponding gene frequencies are: o = 66.7, A = 27.3, B = 6.0. Bernstein's test does not reveal any significant departure from expectation. There is no significant variation in the relative proportions of 0 and A throughout the area. • 3. The percentage frequencies of the blood groups in the north Welsh counties are: 0 = 48.0, A = 39.6, B = 9.2, AB = 3.3. The gene frequencies are: 0 = 69.2, A = 24.4, B = 6.4. Bernstein's test does not reveal any significant departure from expectation. Amongst donors with English family names there is no evidence of heterogeneity in the proportion of 0 and A throughout the area. In the case of donors with Welsh family names there is some evidence of slight heterogeneity. This does not follow any simple geographical pattern and is trivial compared to the large difference between donors of the two classes. • 4. The suggestion of Fisher and Vaughan (1939) that recent population movements can lead to association between blood -group frequencies and family namesis amply substantiated. This simple method of study is shown to possess great `value in the eludication of racial differences. Tn the west country material donors bearing names with the prefixes "Mac" and "0" are much lower in A than the remainder. • 5. In the north Welsh material the percentage of donors of groups 0 and A are: Welsh family names O = 51,2 A = 35.7; Non-Welsh family names O = 45.4 A = 42.7. The difference is highly significant. The former figures are similar to those found in Scotland and Ireland, the latter to the figures for southern England. • 6. Donors with names more characteristic of North Wales are significantly lower in A than donors with names more characteristic of south Wales. Donors with Welsh names resident in the Bristol and Cheltenham areas (and doubtless overwhelmingly of south Welsh origin) are no lower in A than the remainder of those populations. Samples from Cardiff and Swansea do not reveal a low proportion of A. It is concluded that there is strong evidence for believing that while the north Welsh are kin, serologically speaking, to the Scots and the Irish, sharing with them the lowest proportion of A in Europe, the southern Welsh are almost indistinguishable from the southern English. • 7. Cornish donors, even those bearing characteristically Cornish names, are no lower in A than the rest of the population of southern England. • 8. There are no significant age differences between donors of the four groups, either in the case of men or of women. This indicates that if any selective differences distinguish the blood- groups they must be minute between the ages of about 18 to 60 at least. • 9. In the south-western material there is a sex - difference. Women, as compared with men, are slightly more often of group 0 and less often of group A. The tentative hypothesis is advanced that here, for the first time, is evidence that the blood -groups do possess selective value. The difference would be explained if at the early critical stages of high mortality, when considerably more boys are dying than girls, A children had a greater chance of survival than 0 children. This effect cannot persist into adult life, however, as is shown by the absence of any difference in mean ages between donors of the four groups. The sex -difference might be due to homozygotes being at a slight disadvantage compared with heterozygotes; this is precisely the kind of mechanism which would explain the persistence of a polymorphism as old as the species.LIST OF PUBLISHED WORKS SUBMITTED TOGETHER WITH MANUSCRIPT PART OF THESIS: Book: An Introduction to Medical Genetics. Oxford Medical Publications. 1940. • • Papers: Studies on a Child Population - I. Definition of the sample, method of ascertainment and analysis of the results of a group intelligence test (With R.M. Norman & Ruth Griffiths). Annals of Eugenics. Lond. 6: 319. 1935. • II. Retests on the Advanced Otis and Stanford-Binet Scales with notes on the use of a shortened Binet scale (with Ruth Griffiths). Ibid. 8: 15. 1937. • III. Intelligence and Family Size. (with R.M. Norman & Ruth Griffiths) . Ibid. 8: 175. 1937. • IV. The form of the lower end of the frequency distribution of Stanford-Binet intelligence quotients and the fall of low intelligence quotients with advancing age. (with R.M. Norman & Ruth Griffiths) . Ibid. 8: 319. 1937. • V. The resemblance in intelligence between sibs. Ibid. 10: 293. 1940. • • Sex-linked microphthalmia sometimes associated with mental deficiency. Brit. Med. Jour. 2: 1213. 1937. • • A study in the variability in the incidence of rheumatic heart disease within the City of Bristol. (with C. Bruce Perry). Brit. Med. Jour. (Supplement) 2: 1 54. 1937. • • The place of genetics in the practice of medicine. Newcastle Med. Jour. 17: 1 1 5. 1937. • • Intelligence and family size. Eugen. Rev. 30: 237. 1939. • • Observations on a representative group of children of school age, with an account of some family and social characteristics of the brightest, the average and the dullest. Proc. Amer. Assoc. on Mental Deficiency. 44: 79. 1939. • • Does poliomyelitis affect intellectual capacity: an investigation on 98 cases. (with R.G. Gordon and Ruth Griffiths). Brit. Med. Jour. 2: 803. 1939. Surnames, intelligence and fertility. Nature. 145: 939. 1940 • • . Inheritance of mental deficiency. Proc. Seventh International Genetical Congress. 249. 1 941 . Surnames and blood-groups, with a note on a probable remarkable difference between north and south Wales. Nature. 149: 138. 1942. • • Blood-group frequencies in north Wales. Ann. Eugen. London. 11 : 260. 1942 .