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Blood group distribution in natal Preliminary note
408 TRANSACTIONSOF THE ROYAL SOCIETYOF TROPICAL MEDICINE AND HYGIENE. Vol. 52. No. 5. September, 1958.
BLOOD GROUP DISTRIBUTION
IN NATAL
PRELIMINARY NOTE BY
H. HIRSCH, M.B., B.Ctt.* Rhesus Laboratory, Natal Provincial Administration, Durban.
T h e province of Natal is possibly the most interesting one of the Union of South Africa in respect of its variety of races living side by side. All racial units in the U n i o n are here encountered in moderately large numbers - - with the exception of the Cape Malays who are restricted to the Cape Province. This preliminary survey on the distribution of blood groups in Natal was done on antenatal specimens received from all sections of the c o m m u n i t y throughout the province. Each specimen constitutes an individual and new sample of blood tested for the first time during the period under observation. As this report is only a preliminary survey, no genotypes, subgroups or rare (private) blood factors will be listed, with the exception of D u and the rough incidence of A z ; the latter not being confirmed b y anti-A 1 of which there was temporarily an insufficient supply. METHODS
Grouping of the ABO system is carried out in this laboratory by a tube method using anti-A, anti-B, and O sera. Isogglutinins are checked in each case. The rhesus factor is determined with two pure anti-D's. Weakly or partially reacting cells are tested with further anti-D's and are submitted to the human antiglobulin test for confirmation of the presence of D u. All specimens are tested with enzyme (trypsin) treated group O cells, genotype R1R2 (CDe/cDE) and O rr (cde/cde), and with saline suspended cells (group O genotype RIR2) at 37 ° C. for the detection of antibodies. All rh-negative specimens and those derived from women with poor obstetric histories are further checked by the indirect antiglobulin reaction (using O R1R2 cells) for the detection of incomplete antibodies. RESULTS
Routine testing for blood groups mainly of antenatal specimens revealed a consistently very high incidence of group B among Indians ; " d " in people of mixed descent - - being very close to " d " in Indians - - occurring only an eighth more than in Africans, thus showing the stronger influence of the dark-skinned element in the local racial admixtures. T h e bloods examined were all collected during the first half of 1957. Figures are * I wish to thank Dr. H. D. Tonking, Provincial Pathologist, for his interest and criticism and for permission to publish this paper. I also wish to thank Mrs. Rose L. Pinder for her valuable technical assistance.
H. HIRSCH
divided according to racial distribution. groups in Natal :
409
T h e r e are four heterogeneous but distinct racial
(i) White p e r s o n s - immigrants from Europe or their descendants ; (ii) A f r i c a n s - usually referred to as N a t i v e s - " . . . members of any aboriginal race or tribe of Africa " (U. of S.A. Yearbook, 1954-55) ; (iii) I n d i a n s - officially described as A s i a t i c s - " natives of Asia and their descendants, mainly Indians and Pakistani . . . " (ibid.) ; (iv) C o l o u r e d -
"...
persons of mixed white and non-white b l o o d . . .
" (ibid.).
TABLE. Incidence of blood groups in Natal (expressed in percentages) according to racial distribution. A
B
AB
0
A2
A2B
D
d
Du
No. of cases
White
39.5
11.7
4.0
44.8
!
African
28.3
20.8
4.6
46.3
i(4)
Indian
21.8
32.1
7.1
39.
(2)
Coloured
33.6
18.4
5.9
42.
(3)
(3)
(1)
81.0
18.9
0.1
2403
95.3
4.6
0. I
2526
92.8
7.1
0.1
1472
93.3
6.7 . . . .
645
Figures in parentheses indicate numbers of cases so presumed to be (see text) ; they are included as A and AB respectively in the percentage columns. DISCUSSION
White people. T h e population of European origin does not present any problems. It is, as expected, a reflection of an over-all average of people still in that continent, and other continents, such as N o r t h America or Australia, colonized by white pioneers. Africans. T h e incidence of group B is about twice that in Europeans. It seems to matter little whether tribes or groups are assessed separately or jointly in regional surveys. (SHAPIRO, 1951 ; ZOUTENDYK, 1951). T h e low presence of the rhesus factor is confirmed in our table. (SHAPIRO,1951 ; ALTMANN and LEwIs, 1945 ; ZOUTENDYK,1947). Indians. Hindus and Pakistani in Natal would seem to derive mainly from the North of India judging by MOURANT'S figures (1954) on the high incidence there of group B. But, strangely enough, Tamils and Telegus, coming from the South of India, form approximately 54 per cent. of settlers in Natal. (U. of S.A., Dept. of Census and Statistics, 1946). MOURANT (1OC. cit.) gives the wide range of 1.5 per cent. to 12 per cent. for D-negatives. This preliminary review gives a range of 5 . 4 per cent. to 8.4 per cent. Coloured. Group B approximates the African incidence, but " d " is well below that of the Europeans. CONCLUSION A short preliminary survey of the main blood groups found in Natal from carefully tested antenatal specimens is presented. An unexpected finding was a high incidence of group B blood in local Asiatics who in this differ from their relatives in their mother country.
410
BLOOD
GROUP DISTRIBUTION IN
NATAL
I t is h o p e d to publish further findings over a longer period and comprising a larger n u m b e r of examinations which it is felt will be of use to other workers in Africa. REFERENCES
ALTMANN, A. & LEWIS, E. G. (1945). S. Afr. J. med. Sci., 10, 137. MOURANT, A. E. (1954). The Distribution of the Human Blood Groups, p. 104. SHAPIRO, M. (1951). S. Afr. med. J., 25, 165. UNION OF SOUTH.AFRICA, Official Yearbook No. 28 (1954-55), p. 679. (1946). Dept. of Census and Statistics, vol. IV, Table 19, p. 94. ZOUTENDYK,A. (1947). S. Afr. J. med. Sci., 12, 167. (1951). S. _/lfr. med. J., 25, 296.
-
-
-
-
Oxford : Blackwell.
BLOOD GROUP DISTRIBUTION
IN NATAL
PRELIMINARY NOTE BY
H. HIRSCH, M.B., B.Ctt.* Rhesus Laboratory, Natal Provincial Administration, Durban.
T h e province of Natal is possibly the most interesting one of the Union of South Africa in respect of its variety of races living side by side. All racial units in the U n i o n are here encountered in moderately large numbers - - with the exception of the Cape Malays who are restricted to the Cape Province. This preliminary survey on the distribution of blood groups in Natal was done on antenatal specimens received from all sections of the c o m m u n i t y throughout the province. Each specimen constitutes an individual and new sample of blood tested for the first time during the period under observation. As this report is only a preliminary survey, no genotypes, subgroups or rare (private) blood factors will be listed, with the exception of D u and the rough incidence of A z ; the latter not being confirmed b y anti-A 1 of which there was temporarily an insufficient supply. METHODS
Grouping of the ABO system is carried out in this laboratory by a tube method using anti-A, anti-B, and O sera. Isogglutinins are checked in each case. The rhesus factor is determined with two pure anti-D's. Weakly or partially reacting cells are tested with further anti-D's and are submitted to the human antiglobulin test for confirmation of the presence of D u. All specimens are tested with enzyme (trypsin) treated group O cells, genotype R1R2 (CDe/cDE) and O rr (cde/cde), and with saline suspended cells (group O genotype RIR2) at 37 ° C. for the detection of antibodies. All rh-negative specimens and those derived from women with poor obstetric histories are further checked by the indirect antiglobulin reaction (using O R1R2 cells) for the detection of incomplete antibodies. RESULTS
Routine testing for blood groups mainly of antenatal specimens revealed a consistently very high incidence of group B among Indians ; " d " in people of mixed descent - - being very close to " d " in Indians - - occurring only an eighth more than in Africans, thus showing the stronger influence of the dark-skinned element in the local racial admixtures. T h e bloods examined were all collected during the first half of 1957. Figures are * I wish to thank Dr. H. D. Tonking, Provincial Pathologist, for his interest and criticism and for permission to publish this paper. I also wish to thank Mrs. Rose L. Pinder for her valuable technical assistance.
H. HIRSCH
divided according to racial distribution. groups in Natal :
409
T h e r e are four heterogeneous but distinct racial
(i) White p e r s o n s - immigrants from Europe or their descendants ; (ii) A f r i c a n s - usually referred to as N a t i v e s - " . . . members of any aboriginal race or tribe of Africa " (U. of S.A. Yearbook, 1954-55) ; (iii) I n d i a n s - officially described as A s i a t i c s - " natives of Asia and their descendants, mainly Indians and Pakistani . . . " (ibid.) ; (iv) C o l o u r e d -
"...
persons of mixed white and non-white b l o o d . . .
" (ibid.).
TABLE. Incidence of blood groups in Natal (expressed in percentages) according to racial distribution. A
B
AB
0
A2
A2B
D
d
Du
No. of cases
White
39.5
11.7
4.0
44.8
!
African
28.3
20.8
4.6
46.3
i(4)
Indian
21.8
32.1
7.1
39.
(2)
Coloured
33.6
18.4
5.9
42.
(3)
(3)
(1)
81.0
18.9
0.1
2403
95.3
4.6
0. I
2526
92.8
7.1
0.1
1472
93.3
6.7 . . . .
645
Figures in parentheses indicate numbers of cases so presumed to be (see text) ; they are included as A and AB respectively in the percentage columns. DISCUSSION
White people. T h e population of European origin does not present any problems. It is, as expected, a reflection of an over-all average of people still in that continent, and other continents, such as N o r t h America or Australia, colonized by white pioneers. Africans. T h e incidence of group B is about twice that in Europeans. It seems to matter little whether tribes or groups are assessed separately or jointly in regional surveys. (SHAPIRO, 1951 ; ZOUTENDYK, 1951). T h e low presence of the rhesus factor is confirmed in our table. (SHAPIRO,1951 ; ALTMANN and LEwIs, 1945 ; ZOUTENDYK,1947). Indians. Hindus and Pakistani in Natal would seem to derive mainly from the North of India judging by MOURANT'S figures (1954) on the high incidence there of group B. But, strangely enough, Tamils and Telegus, coming from the South of India, form approximately 54 per cent. of settlers in Natal. (U. of S.A., Dept. of Census and Statistics, 1946). MOURANT (1OC. cit.) gives the wide range of 1.5 per cent. to 12 per cent. for D-negatives. This preliminary review gives a range of 5 . 4 per cent. to 8.4 per cent. Coloured. Group B approximates the African incidence, but " d " is well below that of the Europeans. CONCLUSION A short preliminary survey of the main blood groups found in Natal from carefully tested antenatal specimens is presented. An unexpected finding was a high incidence of group B blood in local Asiatics who in this differ from their relatives in their mother country.
410
BLOOD
GROUP DISTRIBUTION IN
NATAL
I t is h o p e d to publish further findings over a longer period and comprising a larger n u m b e r of examinations which it is felt will be of use to other workers in Africa. REFERENCES
ALTMANN, A. & LEWIS, E. G. (1945). S. Afr. J. med. Sci., 10, 137. MOURANT, A. E. (1954). The Distribution of the Human Blood Groups, p. 104. SHAPIRO, M. (1951). S. Afr. med. J., 25, 165. UNION OF SOUTH.AFRICA, Official Yearbook No. 28 (1954-55), p. 679. (1946). Dept. of Census and Statistics, vol. IV, Table 19, p. 94. ZOUTENDYK,A. (1947). S. Afr. J. med. Sci., 12, 167. (1951). S. _/lfr. med. J., 25, 296.
-
-
-
-
Oxford : Blackwell.