ASSOCIATION O F HLA ANTIGENS AND PRIMARY OPEN-ANGLE GLAUCOMA A. R A L P H R O S E N T H A L , M.D., Stanford,
The association between the HLA histocompatibility antigens and primary open-angle glaucoma has been the subject of several investigations with conflicting results. 1 - 7 In an attempt to resolve these conflicts and elucidate those factors which might accounrfor such an associa tion, we studied prospectively the HLA antigenic composition of two groups of patients with primary open-angle glauco ma: those with a known family history of primary open-angle glaucoma and those with no known family involvement. S U B J E C T S AND M E T H O D S
Fifty-five consecutive unrelated white patients with primary open-angle glauco ma from the Glaucoma Service here had HLA typing prospectively. Inquiries about other family members with primary open-angle glaucoma were made of each patient. Twenty-seven individuals indi cated involvement in one or more of their family members (+FHx). Confirmation of familial involvement was made through conversation with the relative's ophthal mologist in 20 of these patients. Twentyeight individuals did not know of any other family member with primary openangle glaucoma (—FHx). The sex distriFrom the Division of Ophthalmology (Dr. Rosenthai) and the Department of Medicine (Dr. Payne), Stanford University Medical Center, Stanford, Cali fornia. This study was supported by funds from the Elsie Ballantyne Fund (Dr. Rosenthal) and NIH Research Grant 9-R01-A1-14438 (Dr. Payne). Read before the Association of Research in Vision and Ophthalmology meeting, Sarasota, Florida, May 1, 1978. Reprint requests to A. Ralph Rosenthal, M.D., Division of Ophthalmology, Stanford University Medical Center, Stanford, CA 94305.
AND R O S E P A Y N E , P H . D . California
bution of the two groups was as follows: —FHx: 22 men, six women; + F H x : 14 men, 13 women. Two control groups were used for com parison (data from Alan Ting, Ph.D., written communication, 1976), detailing the prevalence of HLA antigens in 1,803 American whites (designated Control Group 1) and data on 503 American whites compiled in the 1975 Histocom patibility Workshop 8 (designated Control Group 2). Both groups were thought to be representative of the heterogeneous white population of the United States. We tested 33 HLA antigens, 15 A locus and 18 B locus, with standard micfolymphocytotoxic techniques. Routine chi-square testing with the Yates Correction Factor was used for each antigen to achieve an initial P value (PJ. The corrected P value (Pc) (that value used to determine statistical significance) was then calculated by multiplying Pi for each antigen by the number of antigens typed, that is, P c = Pj x 33. 9 RESULTS
If one compares the antigen frequen cies in either the total group with primary open-angle glaucoma or the subgroup with no known family history with either of the control groups, no increase in any one antigen frequency in patients with glaucoma can be observed (Pt and P c not significant for all antigens) (Tables 1 and 2). We found an increase in the frequency of the HLA-B12 antigen in the group with a family history of glaucoma (48% in the + FHx group, 29% and 24% in Control Groups 1 and 2, respectively). Statistical
AMERICAN JOURNAL O F OPHTHALMOLOGY 88:479-482, 1979
479
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TABLE 1 F R E Q U E N C Y (%) O F HLA-A A N T I G E N S *
POAG HLA-A Al A2 A3 A10 All Aw23 Aw24 A25 A26 A28 A29 Aw30 Aw31 Aw32 Aw33
Total Group (N=55)
+ FHx (N=27)
-FHx (N=28)
Control Group 1 (N = 1,803)
Control Group 2 (N=503)
27 42 25 0 16 4 13 0 13 9 11 7 5 9 4
26 37 30 0 22 0 11 0 7 7 15 7 7 7 7
29 46 21 0 11 7 14 0 18 11 7 7 4 11 0
28 50 26 12 11 4 15 5 7 9 9 9 ND 7 ND
32 49 22 13 8 6 16 7 11 11 7 5 7 8 3
*POAG indicates primary open-angle glaucoma; +FHx, patients with one or more family members with POAG; - F H x , patients with no family members with POAG; ND, not done.
analysis yields a P{= 0.06 with Control Group 1 and a Pi = 0.01 with Control Group 2. However, the P c values of 1.98 (Control Group 1) and 0.33 (Control Group 2) are not statistically significant. No other significant increase in antigen frequency was observed. DISCUSSION
We could not demonstrate an increase in frequency of any of 46 HLA antigens in American whites with primary openangle glaucoma noted in other studies. 3 ' 4 However, we have demonstrated an in crease in the frequency of HLA-B12 anti gen in patients with a family history of primary open-angle glaucoma. This in crease in B12 frequenpy was not statisti cally significant when we used the rigid statistical principle of multiplying the probability obtained from a single 2 x 2 chi-square analysis by the number of an tigens tested. However, there may be an association between B12 antigen and pa tients with a family history of primary
open-angle glaucoma (approximately half the group had the antigen) even though our values are not statistically significant; we may not have achieved statistical sig nificance because of the small number of patients in the + F H x group. To give us statistical significance we would need a chi-square of 9.99. If we compare Control Group 1 (N = 1803; frequency of HLAB12 = 29%) with a + FHx group of 27,16 of the patients would have to possess the HLA-B12 antigen to achieve a chi-square value of this magnitude. Likewise, if we compare Control Group 2 (N = 503; fre quency of HLA-B12 = 24%) with a + F H x group of 27 patients, 15 would have to test HLA-B12 positive to achieve statisti cal significance. The differences from the reported results are three patients in the first instance and two patients in the sec ond instance. These differences could easily be overcome if larger numbers of patients with a family history of primary open-angle glaucoma were studied. This is the third independent study 2 , 4
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HLA ANTIGENS AND OPEN-ANGLE GLAUCOMA
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TABLE 2 F R E Q U E N C Y (%) O F HLA-B A N T I G E N S *
POAG HLA-B B5 B7 B8 B12 B13 B14 B15 B17 B18 Bw21 Bw22 B27 Bw35 B37 Bw38 Bw39 B40 Bw41
+FHx
Total Group (N=55)
(N=27)
-FHx (N=28)
Control Group 1 (N = 1,803)
Control Group 2 (N=503)
18 18 18 35 5 9 7 7 8 4 5 11 13 0 7 6 16 0
4 30 15 48 4 7 7 7 4 0 0 11 15 0 4 0 15 0
29 7 21 21 7 11 7 7 11 7 11 11 11 0 11 11 18 0
11 24 21 29 4 8 10 8 8 6 5 6 18 1 ND
11 23 20 24 6 11 7 7 9 4 5 8 17 5 ND 12f 12 1
9t
12 ND
*POAG indicates primary open-angle glaucoma; + F H x , patients having one or more family members with POAG; - F H x , patients having no family member with POAG; ND, not done. f Reported as B w l 6 .
which has demonstrated an increased fre quency of the HLA-B 12 antigen in a group of patients with primary openangle glaucoma; we believe the associa tion between this antigen and primary open-angle glaucoma may be biologically important because the observed HLAB12 frequency has been the same in all three groups (current study, 48%, N = 2 7 ; Shin and associates, 4 50%, N = 4 0 ; Waltman and associates, 2 55%, N = 16). We investigated only one selection fac tor that may account for such an asso ciation, that is, familial occurrence of the disease. In order to further test the strength and ultimate importance of this association both cross-sectional and long-term follow-up studies in families will be required. Furthermore, other anti gen association, for example, D related and B lymphocyte antigens, should be evaluated to search for other markers.
SUMMARY
HLA testing of 55 patients with pri mary open-angle glaucoma revealed no increased frequencies of any of 17 HLA-A and 29 HLA-B antigens. However, the subgroup with a known family history of primary open-angle glaucoma had an in crease in the frequency of the HLA-B 12 antigen (48%). Intrafamily studies might further define the strength and impor tance of this association. REFERENCES 1. Henley, W. L., Leopold, I. H., and Aviner, Z.: Glaucoma and HL-A antigens. Lancet 2:1273,1974. 2. Waltman, S. R., Palmberg, P., Newton, W., and Becker, B.: Glaucoma HL-A antigens. Lancet 1:927, 1975. 3. Aviner, Z., Henley, W. L., Fortino, M., and Leopold, I. H.: Histocompatibility (HL-A) antigens and primary open-angle glaucoma. Tissue Antigens 7:193, 1976. 4. Shin, D. H., Becker, B., Waltman, S. R., Palm berg, P. F., and Bell, C. E., Jr.: The prevalence of
482
AMERICAN JOURNAL OF OPHTHALMOLOGY
HLA-B12 and HLA-B7 antigens in primary open angle glaucoma. Arch. Ophthalmol. 95:224, 1977. 5. Grabner, G., and Mayr, W. R.: Histokompatibilitatsantigene (HLA-Antigen) und offenwinkelGlaukom. Albrect von Graefes Arch. Klin. Ophthal mol. 202:75, 1977. 6. Kass, M. A., Palmberg, P., Becker, B., and Miller, J. P.: HistocompatibiHty antigens and pri mary open angle glaucoma. A reassessment. Arch. Ophthalmol. 96:2207, 1978. 7. Scharf, J., Gideoni, B., Zonis, S., and Barzilai,
SEPTEMBER, 1979
A.: HistocompatibiHty antigens (HLA) and open angle glaucoma. Ann. Ophthalmol. 10:914, 1978. 8. Payne, R., Feldman, M., Cann, H., and Bodmer, J. G.: A comparison of HLA data of the North American Black with African Black and North American Caucasoid populations. Tissue Antigens 9:135, 1977. 9. Susazuki, T., McDevitt, H. L., and Grumet, F. C.: The association between genes in the major histocompatibility complex and disease susceptibil ity. Ann. Rev. Med. 28:425, 1977.
The association between the HLA histocompatibility antigens and primary open-angle glaucoma has been the subject of several investigations with conflicting results. 1 - 7 In an attempt to resolve these conflicts and elucidate those factors which might accounrfor such an associa tion, we studied prospectively the HLA antigenic composition of two groups of patients with primary open-angle glauco ma: those with a known family history of primary open-angle glaucoma and those with no known family involvement. S U B J E C T S AND M E T H O D S
Fifty-five consecutive unrelated white patients with primary open-angle glauco ma from the Glaucoma Service here had HLA typing prospectively. Inquiries about other family members with primary open-angle glaucoma were made of each patient. Twenty-seven individuals indi cated involvement in one or more of their family members (+FHx). Confirmation of familial involvement was made through conversation with the relative's ophthal mologist in 20 of these patients. Twentyeight individuals did not know of any other family member with primary openangle glaucoma (—FHx). The sex distriFrom the Division of Ophthalmology (Dr. Rosenthai) and the Department of Medicine (Dr. Payne), Stanford University Medical Center, Stanford, Cali fornia. This study was supported by funds from the Elsie Ballantyne Fund (Dr. Rosenthal) and NIH Research Grant 9-R01-A1-14438 (Dr. Payne). Read before the Association of Research in Vision and Ophthalmology meeting, Sarasota, Florida, May 1, 1978. Reprint requests to A. Ralph Rosenthal, M.D., Division of Ophthalmology, Stanford University Medical Center, Stanford, CA 94305.
AND R O S E P A Y N E , P H . D . California
bution of the two groups was as follows: —FHx: 22 men, six women; + F H x : 14 men, 13 women. Two control groups were used for com parison (data from Alan Ting, Ph.D., written communication, 1976), detailing the prevalence of HLA antigens in 1,803 American whites (designated Control Group 1) and data on 503 American whites compiled in the 1975 Histocom patibility Workshop 8 (designated Control Group 2). Both groups were thought to be representative of the heterogeneous white population of the United States. We tested 33 HLA antigens, 15 A locus and 18 B locus, with standard micfolymphocytotoxic techniques. Routine chi-square testing with the Yates Correction Factor was used for each antigen to achieve an initial P value (PJ. The corrected P value (Pc) (that value used to determine statistical significance) was then calculated by multiplying Pi for each antigen by the number of antigens typed, that is, P c = Pj x 33. 9 RESULTS
If one compares the antigen frequen cies in either the total group with primary open-angle glaucoma or the subgroup with no known family history with either of the control groups, no increase in any one antigen frequency in patients with glaucoma can be observed (Pt and P c not significant for all antigens) (Tables 1 and 2). We found an increase in the frequency of the HLA-B12 antigen in the group with a family history of glaucoma (48% in the + FHx group, 29% and 24% in Control Groups 1 and 2, respectively). Statistical
AMERICAN JOURNAL O F OPHTHALMOLOGY 88:479-482, 1979
479
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AMERICAN JOURNAL OF OPHTHALMOLOGY
SEPTEMBER, 1979
TABLE 1 F R E Q U E N C Y (%) O F HLA-A A N T I G E N S *
POAG HLA-A Al A2 A3 A10 All Aw23 Aw24 A25 A26 A28 A29 Aw30 Aw31 Aw32 Aw33
Total Group (N=55)
+ FHx (N=27)
-FHx (N=28)
Control Group 1 (N = 1,803)
Control Group 2 (N=503)
27 42 25 0 16 4 13 0 13 9 11 7 5 9 4
26 37 30 0 22 0 11 0 7 7 15 7 7 7 7
29 46 21 0 11 7 14 0 18 11 7 7 4 11 0
28 50 26 12 11 4 15 5 7 9 9 9 ND 7 ND
32 49 22 13 8 6 16 7 11 11 7 5 7 8 3
*POAG indicates primary open-angle glaucoma; +FHx, patients with one or more family members with POAG; - F H x , patients with no family members with POAG; ND, not done.
analysis yields a P{= 0.06 with Control Group 1 and a Pi = 0.01 with Control Group 2. However, the P c values of 1.98 (Control Group 1) and 0.33 (Control Group 2) are not statistically significant. No other significant increase in antigen frequency was observed. DISCUSSION
We could not demonstrate an increase in frequency of any of 46 HLA antigens in American whites with primary openangle glaucoma noted in other studies. 3 ' 4 However, we have demonstrated an in crease in the frequency of HLA-B12 anti gen in patients with a family history of primary open-angle glaucoma. This in crease in B12 frequenpy was not statisti cally significant when we used the rigid statistical principle of multiplying the probability obtained from a single 2 x 2 chi-square analysis by the number of an tigens tested. However, there may be an association between B12 antigen and pa tients with a family history of primary
open-angle glaucoma (approximately half the group had the antigen) even though our values are not statistically significant; we may not have achieved statistical sig nificance because of the small number of patients in the + F H x group. To give us statistical significance we would need a chi-square of 9.99. If we compare Control Group 1 (N = 1803; frequency of HLAB12 = 29%) with a + FHx group of 27,16 of the patients would have to possess the HLA-B12 antigen to achieve a chi-square value of this magnitude. Likewise, if we compare Control Group 2 (N = 503; fre quency of HLA-B12 = 24%) with a + F H x group of 27 patients, 15 would have to test HLA-B12 positive to achieve statisti cal significance. The differences from the reported results are three patients in the first instance and two patients in the sec ond instance. These differences could easily be overcome if larger numbers of patients with a family history of primary open-angle glaucoma were studied. This is the third independent study 2 , 4
VOL. 88, NO. 3, PART I
HLA ANTIGENS AND OPEN-ANGLE GLAUCOMA
481
TABLE 2 F R E Q U E N C Y (%) O F HLA-B A N T I G E N S *
POAG HLA-B B5 B7 B8 B12 B13 B14 B15 B17 B18 Bw21 Bw22 B27 Bw35 B37 Bw38 Bw39 B40 Bw41
+FHx
Total Group (N=55)
(N=27)
-FHx (N=28)
Control Group 1 (N = 1,803)
Control Group 2 (N=503)
18 18 18 35 5 9 7 7 8 4 5 11 13 0 7 6 16 0
4 30 15 48 4 7 7 7 4 0 0 11 15 0 4 0 15 0
29 7 21 21 7 11 7 7 11 7 11 11 11 0 11 11 18 0
11 24 21 29 4 8 10 8 8 6 5 6 18 1 ND
11 23 20 24 6 11 7 7 9 4 5 8 17 5 ND 12f 12 1
9t
12 ND
*POAG indicates primary open-angle glaucoma; + F H x , patients having one or more family members with POAG; - F H x , patients having no family member with POAG; ND, not done. f Reported as B w l 6 .
which has demonstrated an increased fre quency of the HLA-B 12 antigen in a group of patients with primary openangle glaucoma; we believe the associa tion between this antigen and primary open-angle glaucoma may be biologically important because the observed HLAB12 frequency has been the same in all three groups (current study, 48%, N = 2 7 ; Shin and associates, 4 50%, N = 4 0 ; Waltman and associates, 2 55%, N = 16). We investigated only one selection fac tor that may account for such an asso ciation, that is, familial occurrence of the disease. In order to further test the strength and ultimate importance of this association both cross-sectional and long-term follow-up studies in families will be required. Furthermore, other anti gen association, for example, D related and B lymphocyte antigens, should be evaluated to search for other markers.
SUMMARY
HLA testing of 55 patients with pri mary open-angle glaucoma revealed no increased frequencies of any of 17 HLA-A and 29 HLA-B antigens. However, the subgroup with a known family history of primary open-angle glaucoma had an in crease in the frequency of the HLA-B 12 antigen (48%). Intrafamily studies might further define the strength and impor tance of this association. REFERENCES 1. Henley, W. L., Leopold, I. H., and Aviner, Z.: Glaucoma and HL-A antigens. Lancet 2:1273,1974. 2. Waltman, S. R., Palmberg, P., Newton, W., and Becker, B.: Glaucoma HL-A antigens. Lancet 1:927, 1975. 3. Aviner, Z., Henley, W. L., Fortino, M., and Leopold, I. H.: Histocompatibility (HL-A) antigens and primary open-angle glaucoma. Tissue Antigens 7:193, 1976. 4. Shin, D. H., Becker, B., Waltman, S. R., Palm berg, P. F., and Bell, C. E., Jr.: The prevalence of
482
AMERICAN JOURNAL OF OPHTHALMOLOGY
HLA-B12 and HLA-B7 antigens in primary open angle glaucoma. Arch. Ophthalmol. 95:224, 1977. 5. Grabner, G., and Mayr, W. R.: Histokompatibilitatsantigene (HLA-Antigen) und offenwinkelGlaukom. Albrect von Graefes Arch. Klin. Ophthal mol. 202:75, 1977. 6. Kass, M. A., Palmberg, P., Becker, B., and Miller, J. P.: HistocompatibiHty antigens and pri mary open angle glaucoma. A reassessment. Arch. Ophthalmol. 96:2207, 1978. 7. Scharf, J., Gideoni, B., Zonis, S., and Barzilai,
SEPTEMBER, 1979
A.: HistocompatibiHty antigens (HLA) and open angle glaucoma. Ann. Ophthalmol. 10:914, 1978. 8. Payne, R., Feldman, M., Cann, H., and Bodmer, J. G.: A comparison of HLA data of the North American Black with African Black and North American Caucasoid populations. Tissue Antigens 9:135, 1977. 9. Susazuki, T., McDevitt, H. L., and Grumet, F. C.: The association between genes in the major histocompatibility complex and disease susceptibil ity. Ann. Rev. Med. 28:425, 1977.
