ABH secretor and Lewis type frequencies in an Icelandic series.

The investigation of the secretion of ABH blood group substances in a series of 228 Icelandic indi- viduals resulted in finding that certain ethnic groups in Europe have secretor/non-secretor ratios outside the most often quoted overall figures (Nerell, 1963;Race and Sanger, 1968).One hundred and eleven of the individuals tested came from two villages, Selfoss (centre 1) and Grindavik (centre 2) not far from Reykiavik.At these two centres the individuals tested were all blood donors but they were random as far as ABO groups were concerned.The samples were tested in London for ABO, Lewis, and secretor status.The remaining 117 samples (centre 3) consisted of patients and hospital staff (doctors, nurses, and medical students) from the University Hospital Reykjavik.Birth places of these individuals are spread all over the country and only about 35%were born in Reykjavik.The blood and saliva samples were tested in Reykjavik.The red cells were tested for ABO groups but no Lewis typing was carried out. MethodsThe ABO groups, Lewis types, and tests for ABH in saliva were determined as described in the preceding paper (Lincoln and Dodd, 1972). Results and DiscussionThe results obtained for the frequencies of secretors and non-secretors at each centre are shown in Table I.It will be seen that the overall frequency of the non-secretor phenotype reaches the very high figure of 41.23%.This high figure is in part, due to the large number of non-secretors found at centre 2. The average figure for the other two centres is 35.27%.A possible explanation for the higher percentage of non-secretors at centre 2 (Grindavik) is that a considerable number of the donors from this