Vox Sang. 20: 500-508 (1971)

The Inheritance of the Rh Blood Groups

I. Frequencies in 1,000 Unrelated Caucasian Families Consisting of 2,000 Parents and 2,806 Children

MARION LEWIS, HIROKO KAITA and B. CHOWN

Rh Laboratory, Winnipeg

Abstract. One thousand unrelated Caucasian families (2,000 parents and 2,806 chil- dren) were extensively and intensively Rh typed. The resulting phenotype and estimated gene frequencies do not differ significantly from other large Caucasian series (England, Sweden, Canada). Except for 2 children inheritance accorded with expectation. No evidence of crossing-over or of mutation was forthcoming.

This report is the first of several on observations we have made on the inheritance and expression of Rh blood groups: it deals with frequencies, comprising as i t does, observations on 1,000 unrelated Caucasian families, the 2,000 parents and 2,806 children.

Ascertainment

Most of the families live in the Province of Manitoba; nearly all are Canadian, a few American; all are Caucasian. The ascertainment of the first 900 families has been recorded [6] . Of the remaining 100, 57 were tested because of twinning, 18 because of a genetic condition, while 25 were friends of ours. No family was selected because it had a particular Rh type, so the series may be considered random for Rh. A few children were omitted when shown by 2 or more blood group systems not to be the children of the putative parents.

Sera and Methods

All samples were first tested with the following sera by the saline capillary method(1); anti-Ce (Bill or Kai), anti-c (Nob, Vau/4 or Keo/4), anti-E (McL or Tow),

Supported by a grant from the Medical Research Council of Canada.

Received: January 4, 1971; accepted: January 14, 1971.

The Inheritance of the Rh Blood Groups 501

anti-e (Stur/4), anti-D (And/2O or Fra/20), anti-Cw (Kra or Har). These particular sera were selected either because in saline they gave nice distinctions of zygosity, or because, through not reacting by this method but reacting by the papain capillary method, they led to certain rare genes being brought to light. All specimens that were negative in this first run were then tested by the papain

capillary technique [5] as follows: all Ce-negative were tested with the serum Bill; all c-negative with an additional anti-c, either Gai or Ale; all E-negative with the sera McL or Orv; all E-positive and all e-negative with additional anti-e serum Da/40; all D-negative with serum Cha or Bal and with serum McLag.

When the results Wered in the 2 stages of testing, samples from the family were tested extensively with the above sera and with others by saline, papain and indirect Coombs methods. In all cases there turned out to be a genetic reason for the observed difference.

Of the 4,806 samples 3,699 were tested with anti-f (Ort/16) and 2,123 with anti-DW (Bill abs x RIR1 cells), both by the papain capillary method.

For brevity we will, from here on, use ‘saline-positive (or negative)’ for reacted (or did not react) by the saline capillary method, and ‘papain-positive (or negative)’ for reacted (or did not react) by the papain capillary method.

Results

1 . Frequencies of the Recognized Rh Genes The Rh types of the 2,000 parents are set out in table I. The fre-

quencies of the 9 genes shown were arrived at by simple gene count. R Z was assumed in preference t o ry. For the purpose of the analysis we have included DU with D and CW with C. The data are internally consistent and do not differ significantly from a survey of 3,100 Mani- tobans made 21 years ago using anti-C, -c, -D and -E (2), or from an English (7) or a Swedish (3) population sample (table 11).

2. Inheritance of the Recognized Rh Genes The Rh types of the 1,000 families are set out in table 111. The

agreement with expectation is good: the phenotypes of only 2 children (the R, children marked with an asterisk in mating types 7 and 28) differ from common expectation. In both cases it is the father’s Rh gene that is not represented, so illegitimacy is the most likely ex- planation.

There is no evidence in these families for crossing-over or mutation, nor is there evidence for crossing-over in an additional 110 families related to the present ones. However there is evidence for a possible mutation in one of these related families. Details wil l be published separately.

502 LEWIS/KAITA/CHOWN

Table I. Rh types of the 2,000 parents

Phenotype Observed Expected XP Gene

Number Frequency Frequency Number frequencies

361 261 63 678 267 33 306 17 10 2 1 1 0

0.1805 0.1305 0.0315 0.3390 0.1335 0.0165 0.1530 0.0085 0.0050 0.0010 0.0005 0.0005 0.0000

0.1761 0.1394 0.0276 0.3383 0.1326 0.0176 0.1530 0.0085 0.0047 0.0006 0.0003 0.0002 0.0011

352.2 278.8 55.2 676.6 265.2 35.2 306.0 17.0 9.4 1.2 0.6 0.4 2.2

0.22 1.14 1.10 0.00 0.01 0.14 0.00 0.00 0.04 0.53 0.27 0.90 2.20

R' 0.4090 RQ 0.1602 Ro 0.0218 Rz 0.00075 ' i i o 0.00025 r 0.3912 r' 0.0108 r e 0.0060 ry 0.0000

2000 1.0000 1.0000 2000.0 6.55 1.0000

n = 7 P approx. 0.5

Table II. Comparison of calculated gene frequencies for Manitoba in 1949 and at present; England in 1945; Sweden in 1966

Gene Study

Manitoba Manitoba England Sweden 1949 (2) 1970 1945 (7) 1966 (3) N=3100 N=2000 N=2000 N=8297

0.3946 0.01M

0.4348 0.4090 0.3955 0.3912 0.1287 0.1602 0.0191 0.0218 0.0073 0.0060 0.0124 0.0108 0.0022 0.00075

0.00025

0.#76 0.0129 0.4205 0.3886 0,1411 0.0257 0.0119 0.0098 0.0024

0.4036 0.0198 0.4234 0.3821 0.1670 0.0186 0.0029 0.0052 0.0008

Tabl

e II

I. T

he o

bser

ved

and

expe

cted

mat

ings

and

children

aris

ing

ther

efro

m

Mat

ings

C

hild

ren

Typ

e N

O.

x* T

R

, R

l&

R,

Rlr

&

r Ro

r r’

r r”

r r’

r’

r”r”

r’r

” R

IRz R

,Rz

E,,r

R&

xz

1

Rlx

Rl

2 x R

,R,

3 x R

,

4 x

R,r

5 x

R,r

6 x

Ro

7 x

r

8 x

r’r

9 x

r”r

34

111

31.1

0.27

42

12

1 49

.1

1.03

13

69

9.7

1.

12

119

301

119.

2 0

50

174

46.6

0.25

3

12

6.2

1.65

61

15

5 53

.9 0.

94

3 6

3.0

2 5

1.7

111

110.

91

64

57

60.5

0 60

.44

69

69.0

14

2 15

0.50

89

87

.00

1*

0 4 2.90

1

2.43

158

146.

98

84

84.9

5 12

11

.85

154

151.

13

2 2.90

4 2.

43

0.09

0.06

1

3.52

1

2.05

0.15

3.87

0.10

0.1

0

0.07

10

R

l&xR

IR,

14

36

7 22

7

19.4

1.50

9

18

9 11

xR

, 13

30

17

13

7.

7 3.

65

15

15

12

xRlr

89

24

2 53

70

55

62

1

1

13

xR,r

31

91

22

27

19

22

1

94.2

0.

29

60.5

60

.5

59.1

0 58

.52

1.40

1.98

37.0

0.

97

22.7

5 22

.75

22.1

9 22

.01

0.56

0.74

4.9

7.59

8.

41

8.33

0.

09

0.17

14

xRo

11

17

89

0.07

0.09

0.46

0.00

3.11

2 0.

60

0.15

$?

3.92

0.80

2 r E ,, ;

P. !2 G

1.77

0.54

3.51

rn

0

W

2.36

1.00

Tab

le 1

11 (

con

tin

ued

)

Mat

ings

C

hild

ren

NO

. xa

T

R

, R

IR,

R,

Rlr

R

,r

Ro

r r'r

r"

r r'r

' r"

r" r

'r"

R,R

, G

Rz 3s

R2Z

o X~

Type

cn 0

rp

15

xr

16

x r

'r

17

x r"

r

18

x R

,r

19

x R

BR

z

20

R2x

R,

21

x R

lr

22

x R$

23

x r

24

x r"

r

25

Rlr

xRlr

26

xR

g

27

x R

o

28 XI

29

x r'r

42

96

42.7

0.01

1

2 2.

4 1 3

1.3

2 5

0.2

1 2

0.1 2

11

0.8

19

47

18.7

0.

00

8 24

7.

3 0.

07

5 14

8.

5 1.

44

1 1

0.2

113

321

114.

4 0.

02

92

282

89.8

0.

05

10

38

11.9

0.

30

109

271

103.

7 0.

27

11

31

41

55

46.7

6 46

.31

1.24

1.

69

5.27

1 1

0.48

0.

48

0.48

0.

48

0.02

0.

02

0.02

0.

02

11

1

0.75

0.

69

0.75

0.

69

0.06

0.

06

1 3

1

1.25

1.

25

1.25

1.

25

0.50

0.

50

1 1

0.50

0.

50

11

11.0

19

28

23

.5

22.7

5 0.

75

14

10

12

11.5

9 0.

41

14

13.5

1 0.

49

1 0.50

0.50

69

15

8 6

86

2 80

.25

160.

28

8.41

71

.84

0.22

66

68

72

10

66

70

.50

70.4

2 70

.33

7.53

62

.970

.08

0.17

24

5

9

19.0

0 10

.22

8.78

1*

13

2 8

130

0 13

5.23

7.

45 1

28.0

5 0.

27

10

9 1

83

.

4 w 5 2.

92

1.16

! .

n 4

0.51

5.31

1.61

4.00

0.41

4.22

5.

7 4.

93

7.75

8.

16

0.41

7.

34

7.34

30

x r"

r

31

R,rx

R,r

32

x R,

33

x r

34

x r'r

35

x r"

r

36

Rox

r

37

rxr

38

x r'r

39

x r"

r

40

R,K

,~R

,~

32

Oth

er

mat

ings

3 9

3.2

17

60

17.6

0.

02

4 16

4.6

45

11

8 40

.5 0.

50

1 2

2.2 1

3 1.3

5

18

5.4

0.03

18

52

23

.4

1.25

1

3 2.6

2

5 1.4

1

2 0.1

0 6.

3

2.25

22

15.0

0

1 0.50

0.75

1 0.50

3 4

2 2.

25

0.14

2.11

0.

14 2

.11

23

1 14

29

.92

1.70

13

.30

0.08

6

5 5

8.

00 4

.26

3.74

54

64

58

.86

3.21

55.7

9 0.

14

1 0.02

0.5

0 0.

02

0.48

0.48

1

2 0.

81

0.06

0.69

0.

69

12

6 52

52

9.33

8.

67

12

1.

5 1.

5 5 2.

5 2.

5

0.50

5.28

1.05

4.96

Tot

al

1,00

0 2,

806

463

436

96

934

357

48

450

11

5 0

0 0

4 1

1 0

482.

79 4

34.1

0 87

.19

935.

04 3

54.3

6 52

.74

419.

76 2

2.62

12.

48 0

.21

0.06

0.

15

1.75

1.

75

0.50

0.

50

0.81

0.

01

0.89

0.

00

0.02

0.

43

2.18

5.

97

4.48

0.

24

xa 29

.08 n =

23 0

.10 <

P < 0.2

5 T

otal

15

.03

n =

9 P

app

rox.

0.1

0

Exp

ecte

d gi

ven

in it

alic

s. T

otal

exp

ecte

d nu

mbe

r of

chi

ldre

n of

eac

h ph

enot

ype

amve

d at

by

addi

tion.

506 LEWIS/KAITA/CHOWN

Table IV. The f types of 734 families

Mating8 Children

Type No. xa T f+ f-

f+ x f+ 321 0.10 1016 888 128

f+ x f- 335 0.04 932 580 352

f- x f- 78 0.96 283 0 283 87.13 0 283

315.32 876.91 139.09

331.55 586.60 345.40

Total 734 1.10 2231 1468 763 1463.51 767.49

n = 2 P approx. 0.50

Table V. Cw types of 1,000 families

Matings Children

Type No. T C W+ C W -

~~

cw+ x cw+ 1 2 2 0

cw+ x c w - 55 152 72 80 55.6 76 76

c w - x c w - 944 2,652 0 2,652 943.6 0 2,652

0.8 1.5 0.5

Total 1,000 2,806

3. Inheritance of the Antigen f (ce, hr) While our supply of anti-f was adequate all families were tested with it. The results for 734 families are set out in table IV; expectation is based on the gene frequencies of table I. All f-positive samples were c and e positive, and in all informative families the f-positive reaction occurred only when c and e were in the cis position.

The Inheritance of the Rh Blood Groups 507

4. Uncommon and Rare Antigens and Genes CW. Fifty-seven of 2,000 parents (2.85 % ) and 74 of 2,806 children

(2.64%) were Cw-positive. The family results set out in table V are consistent with expectation based on parental frequency.

CX and Rz. In this series the presence of CX would be recognized only when it was not partnered with C. Of 960 parents heterozygous for C 956 were C saline-negative, papain-positive. Three of the re- maining 4 were CE while the 4th and 1 of his 2 children were CX as proved by sera Troll and Mercer. The frequency of CX is therefore of the order of 1 in 1,000. STRATTON and RENTON [8] found 4 in 3931 (1 in 983) unrelated Cc English people to be CX positive.

The CE parents (mating types 18 and 19) carried either Rz or r y .

Chance favors Rz. Further had r y been present there would probably have been a weakened expression of D [4] whereas the D reactions were normal. The R,r parents must have carried r or RO since they were f (ce) positive.

E w . Samples that were E saline-negative, papain-positive were tested with anti-EW (TG): none was positive, all being examples of weakly reacting E antigens.

D W 453 families comprising 906 parents and 1217 children were tested with anti-DW: all were negative.

r G . This complex would have been recognized only in the D-neg- ative, DU-negative, DCG-positive samples, of which there were 17. All gave normal reactions for r‘r, no example of r G being found. A modifying-gene-dependent cbrG” was found in one of the related fami- lies. This will be the subject of a separate report.

R o . By our methods the first hint of the presence of this gene in the heterozygote comes not from a strong anti-D reaction but from a slow, i.e. single dose, reaction with a n t i 4 and -e or anti-c and -e when, from the phenotype, one might expect a double dose reaction. In only one family (mating type 40) was this observed. (Supporting evidence for the presence of RO in this family will be given in the next paper.) The apparent frequency of ZO in the sample is therefore 1 in 4,000 parental genes or 0.00025, which is not significantly dif- ferent from Heiken and Rasmuson’s estimate of 0.0005-0.0006 for a Swedish population sample [3].

‘Weak’ E and e. Bloods of phenotype R,r and r“r were occassionally saline-negative, papain-positive with anti-E or -e or both. For the purposes of the present paper these have been classed simply as posi- tive for the particular antigen or antigens.

-

508 LEWIS/KAITA/CHOWN

Acknowledgements

We are indebted to Dr. IRENE U C H I ~ ~ A for supplying many of the samples and to numerous friends and their families for others. For gifts of sera we are indebted as follows: Dr. PHILIP LEVINE, anti-f; Dr. PHILLIP STURGEON, anti-e; Dr. TIBOR GREENWALT, anti-EW; Dr. C. M. GILES, serum Troll; Dr. T. E. CLEGHORN, se- Mercer.

References

1. CHOWN, B.; LEWIS, M., et PETERSON, R. F.: Sur In valeurd’une methodeutilisant un tube capillaire inclinC pour caracteriser le facteur Rh. Rev. HCmat. 4: 605-607 (1949).

2. CHOWN, B.; PETERSON, R. F.; LEWIS, M., and HALL, A.: On the ABO gene and Rh chromosome distribution in the white population of Manitoba. Canad. J. Res. E. 27: 214-225 (1949).

3. HEIKEN, A. and RASMUSON, M. : Genetical studies on the Rh blood group system. Hereditas 55: 192-212 (1966).

4. MCGEE, R.; LEVINE, P., and CELANO, M.: First example of genotype ryry- a family study. Science 125: 1043 (1957).

5. LEWIS, M.; KAITA, H., and CHOWN, B.: Kell typing in the capillary tube. J. Lab. clin. Med. 52: 163-168 (1958).

6. LEWIS, M.; KAITA, H., and CHOWN, B.: The inheritance of the Kell blood groups in a Caucasian population sample. Vox Sang. 17: 221-223 (1969).

7. RACE, R. R.; MOUIUNT, A. E.; LAWLER, S. D., and SANGER, R. : The Rh chromo- some frequencies in England. Blood 3: 689-695 (1948).

8. STRATTON, F. and RENTON, P. H.: Haemolytic disease of the newborn caused by a new Rh antibody, anti-Cx. Brit. med. J. i: 962-965 (1954).

Authors’ address: Miss MARION LEWIS, Mrs. H. KAITA and Dr. B. CHOWN, Rh Laboratory, 735 Notre Dame, Winnipeg 3 (Canada)