Tissue Antigens (1979), 14,251-255

HLA Markers in Six Lebanese Religious Subpopulations Jean-Louis Serre' , Gkrard Lefranc2, Jacques Loiselet3 and Albert Jacquard'

' Genetic Department of National Institute of Demographic Studies, INED Pans, France, Faculty of Pharmacy, Monastir, Tunisa, and 3French Faculty of Medicine and Pharmacy of Beyrouth, Lebanon A total of 315 normal, unrelated individuals from six of the seven principal religious communities of Lebanon have been typed for 26 alleles of the A and B loci. The gene, haplotype frequencies and A values have been calculated. The HLA gene frequencies for loci A and B reported in this study are shown to cross MoslimChristian lines, but generate a distinguishably different profile for the Armenian immigrant subpopulation. This first-level homogeneity which is inconsistent with results earlier reported for ABO, rhesus and Gm systems, seems to disappear when linkage disequilibrium deltas are compared. Received for publication 1 I December 1978, revised, accepted 7 May 1979

There are few data concerning immunogenetic markers in the Lebanese population at the present time. The investigation by Bashir et al. (1972) concerned only three Christian subpopulations. No data have so far been reported concerning immunogenetic markers among Armenians and Moslem Lebanese subpopulations. The principal aim of the present work was to provide the antigenic profile of all these subgroups living in Lebanon. A second aim was t o discover whether the religious diversity, resulting from an eventful socio-political history, might be associated with a biological diversity. Biological differences have been reported for ABO, Rhesus, Gm or enzymatic systems 0001-2815/79/080251-05

(Ruff% & Taleb 1965, Lalouel et al. 1976, Lefranc et al. 1978).

Material and Methods The investigation was carried out on 315 unrelated Labanese living in Beirut and belonging to a Christian community Maronites (69), Catholic Greeks (48), Orthodox Greeks (SO), Armenians (51), or a Moslem one, Sunnites (48), Shiites (49). No data could be collected for the Druze Mohammedan community. HLA typing was performed using the microlymphocytotoxicity test (Terasaki & McClelland 1964). HLA sera were provided by Prof. J. Dausset (Paris) and specificities according to the

$02.5010 0 1979 Munksgaard, Copenhagen

2 52

SERRE ET AL.

present HLA nomenclature are shown in Table 1.

Results The calculated gene frequencies and main A values among the six subpopulations are respectively shown by Tables 1 and 2. Calculations. Gene frequencies ( p ) were Biological heterogeneity between comcalculated by the following formula: munities has been tested by homogeneity chi-square tests (Table 3). P = 1--

where f is the frequency of positive individDiscussion uals. The linkage disequilibrium (A) was N o significant difference is observed estimated according to the equation Of between HLA-A and B frequencies of Mattiuz et al. (1970). Lebanese communities, Armenians ex-

Table 1 Gene fiequenn'es in Lebanese subpopulations

HLA Sample Size

A 1

2 3 9 10 11 28 29 Aw30 t 31 w32 blank B 5 7 8 12 13 14 15 17

18 w21 w22 27 w35 w38 40 blanc

Gene frequencies (%) Maronites (Ma) 69 7.2 25.4 12.3 13.7 8.7 2.2 8.7 3.6 7.2 2.2 8.8 13 2.9 0.7 10.1 2.9 4.3 1.5 2.9 7.2 8 3.6 1.5 24.6 2.2 0.7 13.9

Catholic Greeks (C.G.) 48 17.7 21.9 14.6 12.5 3.1 3.1 9.4 3.1 6.2 3.1 5.3 9.4 4.2 1 8.3 6.2 2.1 5.2 2.1 12.5 11.9 3.1 0 19.8 3.1 0

11.5

Orthodox Greeks (O.G.) 50

Sunnites (Su) 48

14

15.7 21.9 15.6 7.3 7.3 5.2 7.3 3.1 9.4 2 5.2 10.4 1 4.2 5.2 4.2 2 3.1 2 3.1 11.5

14 4 22 7 6 11 2 8 5

7 13 0 1 7 5 4 3 1 6 14 3 1 30 2 2 8

5.2

3.1 29.2 4.2 0

11.6

Shiites (Sh) 49 14.3 17.3 14.3 21.4 7.1 3.1 6.1 13.1 7.1 1 5.2 6.1 6.1 2 4.1 11.2 3.1 2 3.1 7.1 5.1 4.1 4.1 27.5 3.1 2 9.2

Armenians (Ad 51 21.6 26.5 10.8 17.6 7.8 5.8 2.9 2 3.9 1 0.1

6.9 6.9 2 9.8 6.9 1 2 2.9 12.8 8.8 2.9 1 27.6 2.9 2 3.9

lo’.

(*: P

< .05-**:

P

Maronites

19***

-

Greeks catholic

-

17*** 25***

-

Greeks orthodox Sunnites

46***

-

-

31***

27*** 30**

-

Shiites

Table 2 characteristically significant A values for haplotypes encountered in s i x Lebanese subpopulations

P < .ool.) < .02 -)

c**: P < .01-****:

A values X

+ + +

B8 Bw17 Bw21 Bl8 A10, B13 A l l , B7 A l l , B13 A l l , Bw17 A l l , Bw22 A28,814 A29, B7 Aw32, B8 Aw32, B14 Aw30 31, B13 Aw30 31, B27 Aw30 31, B35

Al, Al, A2, A9,

Haplotypes

Most

Armenians

z

F

254

SERRE ET AL.

cepted (Table 3). This is not surprising, since Armenians originated in the northern Middle-East and arrived only recently in Lebanon. The high degree of polymorphism in the HLA system requires testing of larger samples to show significant differences. Paradoxically, the similar profile among Lebanese communities may be a consequence of this condition. This first level homogeneity, which is inconsistent with results earlier reported for ABO, Rhesus and Gm systems (Lalouel et al. 1976), seems to disappear when linkage disequilibrium delta values are compared. When using delta values in the comparison of populations, a cautionary note is necessary since the sample sizes are small. Table 2 shows that all but a few Sunnite haplotype frequencies are at equilibrium, for only a few significant A values are observed. It might be a consequence of engogamy. It would be very interesting to type the Druze subpopulation, the most

endogamic of all, in order to see whether significant A values are numerous or not. All the Christian subgroups show the Aw30 -I-31 - B13 disequilibrium previously reported by Bashir et al. (1972), but Sunnites and Shiites d o not. The A l l B13 disequilibrium, not reported by Bashir et al., is also shared by all Christians subgroups, Armenians excepted. But the A value analysis failed to show a clear differentiation between Christians and Moslems as reported by Lalouel et al. (1976). It must be noted that the only negative association (Aw30 -t 31 - B35) is observed among Shiites and Armenians; the relative closeness of these two communities has previously been reported in a cluster analysis (Serre 1976). A statistical difference exists between results of the present study and results of Bashir et al. (1972) from a sample of 150 Lebanese Christians living in Sydney, Australia (Serre 1976). This should disappear when a large sample is analyzed in each subpopulation.

Table 3 Significance of chi-square test of homogeneity for each pair of communities at each A & B locus Ma

O.G.

su Sh Ar

N N

A

N

N

N

N

A B

N N

N N

N

A B

N

N

N

N

N

A

t*tt

*

B

N

N

N : no significance.

*: P < .05. ' I :

to..

P

O.G.

B

A

C.G.

C.G.

< .02.

. P < .01. ttt.. . P < .001.

*

su

Sh

N

N N

N N

** ttt

N N

LEBANESE HLA MARKERS

Nevertheless, the high frequency of Bw3 5 is a distinctive feature of the entire Lebanese population. This high frequency is close to that observed in the Italian population (Bodmer et d. 1972) or in the Turkish group of Svejgaard et al. (1972) and Albert et al. (1972). It would be interesting to pursue the study of HLA throughout the MiddleEast and Mediterranean areas. Acknowledgments We should like to thank Mr. G. Merhej for technical assistance and Mrs. Y. de Cornulier and C. Audit for secretarial assistance. References Albert, E. D., Scholz, S., Rosenthal, I., Bazin, H. & Bertrams, J. (1972) Study of the HLA system in the Turkish and German populations. Histocompatibility Testing, pp. 147152.Munksgaard, Copenhagen. Bashir, H. V., Johnston, J. M., Brotherton, J. V. M., Guinan, J. J . , Amos, D. B., Kim, R. & Case, J. (1972)A study of the HLA system in 150 expatriate lebanese domiciled in Sydney. Histocompatibility Testing, pp. 1 3 3137.Munksgaard, Copenhagen. Bodmer, J. G., Rocques, P., Bodmer, W. F., Colombani, J., Degos, L., Dausset, J. Piazza, A. (1972) Joint Report of the Fifth International Histocompatibility Workshop. Populations Studies. Histocompatibility Testing, pp. 621-667. Munksgaard, Copenhagen. Lalouel, J. M., Loiselet, J., Lefranc, G., Chaiban, D., Chakhachiro, L., Rivat, L. & Ropartz, C. (1976) Genetic differentiation among

255

Lebanese communities. Acta Anthropogenetica 1, 15-33.

Lefranc, G., Rivat, L., Serre, J. L., Lalouel, J. M., Pison, G., Loiselet, J., Ropartz, C., De Lange, G. & Van Loghem, E. (1978) Common and uncommon immunoglobulin haplotypes among Lebanese communities Hum. Genet., 41,197-209. Mattiuz, P. L., Ihde, D., Piazza, A., Cepellini, R. & Bodmer, W. E. (1970)New approaches to the population, genetic and segreation analysis of the HLA system. Histocornpatibility Testing, pp. 193-205. Munksgaard, Copenhagen. Ruffie, J. & Taleb, N. (1965) etude himotypologique des ethnies libanaises CNRS, Centre d’himotypologie de Toulouse. Herman, Paris. Serre, J. L. (1976) L’apport de I’etude des systimes HLA dans la description de la rialite‘ anthropobiologique des communaut& libanaises. Tbe‘se de 3ime cycle, Paris VII. Svejgaard, A., Staub Nielsen, L., Jersild, C. Jakobsen, B., Ryder, L. P., Frelesleben, E., Sorensen, H., Henningsen, K., Korsen, G. & Mizan, H. (1972) HLA and other polymorphisms in Turks. Histocompatibility Testing, p. 139.Munksgaard, Copenhagen. Terasaki, P. 1. & McClelland, J. D. (1964)Microdroplet assay of human serum cytotaxins. Nature (Lond.), 204,998-1000.

Address: J. L:Serre & A. Jacquard Institut National d’Etudes Demographiques Service de Ge‘ne‘tique 27 rue du Commandeur 75675 Paris Cedex 14 France

HLA markers in six Lebanese religious subpopulations.

Tissue Antigens (1979), 14,251-255 HLA Markers in Six Lebanese Religious Subpopulations Jean-Louis Serre' , Gkrard Lefranc2, Jacques Loiselet3 and Al...
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