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Is Weinberg's Differential Rule Valid?

Published online by Cambridge University Press:  01 August 2014

William H. James*
Affiliation:
The Galton Laboratory, University College, London

Abstract

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Weinberg's differential method, whereby the frequency of dizygotic twins in a population is obtained by doubling the number of opposite-sexed pairs, might not be valid. Data are presented indicating a higher frequency of same-sexed than opposite-sexed pairs among samples of dizygotic twins ascertained at birth, thus favoring the hypothesis that, contrary to the method's fundamental assumption, the sexes of the two twin zygotes be not independent.

Type
Brief-Report
Copyright
Copyright © The International Society for Twin Studies 1979

References

REFERENCES

1.Buhner, MG (1976): Is Weinberg's method valid? Acta Genet Med Gemellol 25:2528.Google Scholar
2.Corney, G, Robson, EB, Strong, SJ (1968): Twin zygosity and placentation. Ann Hum Genet 32: 8996.Google Scholar
3.Guerrero, R (1970): Sex ratio: A statistical association with the type and time of insemination in the menstrual cycle. Int J Fertil 15:221225.Google ScholarPubMed
4.Guerrero, R (1974): Association of the type and time of insemination within the menstrual cycle with the human sex ratio at birth. N Engl J Med 291:10561059.Google Scholar
5.James, WH (1971): Excess of like-sexed pairs of dizygotic twins. Nature 232:277278.CrossRefGoogle ScholarPubMed
6.James, WH (1971): Cycle day of insemination, coital rate and sex ratio. Lancet 1:112114.CrossRefGoogle ScholarPubMed
7.James, WH (1975): Sex ratio and the sex composition of the existing sibs. Ann Hum Genet 38: 371378.CrossRefGoogle ScholarPubMed
8.James, WH (1975): Sex ratio in twin births. Ann Hum Biol 2: 365378.CrossRefGoogle ScholarPubMed
9.James, WH (1975): Sex ratios in large sibships, in the presence of twins and in Jewish sibships. J Biosoc Sci 7:165169.Google Scholar
10.James, WH (1975): The distributions of the combinations of the sexes in mammalian litters. Genet ResCamb 26:4553.CrossRefGoogle ScholarPubMed
11.James, WH (1976): The possibility of a flaw underlying Weinberg's Differential Rule. Ann Hum Genet 40:197199.Google Scholar
12.James, WH (1976): Timing of fertilization and sex ratio of offspring. Ann Hum Biol 3:549556.Google Scholar
13.James, WH (1976): The combinations of the sexes in twin lambings. Genet Res Camb 28:277280.Google Scholar
14.James, WH (1977): Coital rate, cycle day of insemination and sex ratio. J Biosoc Sci 9:183189.Google Scholar
15.James, WH (1977): The sex ratio of monoamniotic twin pairs. Ann Hum Biol 4:143153.CrossRefGoogle ScholarPubMed
16.Nylander, PPS (1970): Placental forms and zygosity determination of twins in Ibadan, Western Nigeria. Acta Genet Med Gemellol 19:4954.CrossRefGoogle ScholarPubMed
17.Nylander, PPS, Corney, G (1976): Placentation and zygosity of twins in Northern Nigeria. Ann Hum Genet 40:323329.Google Scholar
18.Potter, EL (1963): Twin zygosity and placental form in relation to the outcome of pregnancy. Am J Gynecol 87:566577.Google Scholar
19.Roberts, AM (1972): Gravitational separation of X and Y spermatozoa. Nature 238:223225.CrossRefGoogle ScholarPubMed
20.Roberts, AM (1978): The origins of fluctuations in the human secondary sex ratio. J Biosoc Sci 10:169182.CrossRefGoogle ScholarPubMed
21.Rostron, J, James, WH (1977): Maternal age, parity, social class and sex ratio. Ann Hum Genet 41: 205217.Google Scholar
22.Say, B, Güngör, E, Durmus, Z (1967): The incidence of twin births in Turkey. Turk J Pediatr 9: 3236.Google ScholarPubMed
23.Strong, SJ, Corney, G (1967): “The Placenta in Twin Pregnancy.” Oxford: Pergamon, p 38.Google Scholar
24.Walsh, RJ, Kooptzoff, O (1955): A study of twins. Aust J Exp Biol Med Sci 33:189198.Google Scholar