Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-23T20:45:49.669Z Has data issue: false hasContentIssue false

Sex Differences in Genetic Determinants of Craniofacial Variations - A Study Based on Twin Kinships

Published online by Cambridge University Press:  01 August 2014

K. Sharma*
Affiliation:
Department of Anthropology, Panjab University, Chandigarh, India
*
T-II-44, Sector 25, P.U. Campus, Chandigarh - 160014, India

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Race, sex, nutritional status and cultural factors affect craniofacial morphogenesis. Out of these, sex is a major factor in craniofacial differentiation, because it can be stronger in one ethnic group and weaker in another. In this study, sex differences in genetic variance and heritability of 13 craniofacial traits are investigated. The study is based on a sample of 45 MZ and 101 DZ twin pairs and their 125 singleton siblings, 104 fathers and 103 mothers in 146 families drawn from an urban population of Chandigarh. Results of t'-tests for equality of the means reveal association of zygosity with the mean value of bigonial diameter in female twins and for none in males. Heterogeneity of variance is observed in about 50% traits in females as compared to 15% in males. This invalidates conventional within-pair genetic variance estimates for these traits. The revised genetic variance ratios are higher on an average in males than in females. However, there is greater MZ environmental covariance in male twins than their female counterparts. Family data indicate higher maternal effect for ear height, nasal height and frontal breadth, while greater paternal effect is seen in cranial traits. Sex-wise midparent-child regression coefficients show greater heritability in daughters for nasal traits and bigonial breadth, while sons show higher genetic component for head size measures.

Type
Research Article
Copyright
Copyright © The International Society for Twin Studies 1998

References

REFERENCES

1.Cavalli-Sforza, LL, Bodmer, WF (1971): The Genetics of Human Populations. San Francisco: Freeman.Google Scholar
2.Cheverud, JM, Kohn, LAP, Konigsberg, LW, Leigh, SR (1992): Effects of fronto-occipital artificial cranial vault modification on the cranial base and face. Am J Phys Anthropol 88: 323345.Google Scholar
3.Christian, JC (1979): Testing twin means and estimating genetic variance. Basic methodology for the analysis of quantitative twin data. Acta Genet Med Gemellol 28: 3540.Google ScholarPubMed
4.Christian, JC, Kang, KW, Norton, JA (1974): Choice of an estimate of genetic variance from twin data. Am J Hum Genet 26: 154161.Google ScholarPubMed
5.Christian, JC, Feinleib, M, Norton, JA (1975): Statistical analysis of genetic variance in twins. Am J Hum Genet 27: 807.Google Scholar
6.Christian, JC, Kang, KW, Norton, JA (1977): Comparison of within-pair and among component estimates of genetic variance from twin data. Am J Hum Genet 29: 208210.Google Scholar
7.Christian, JC, Norton, JA (1977): A proposed test of the difference between the means of monozygotic and dizygotic twins. Acta Genet Med Gemellol 26: 4953.CrossRefGoogle ScholarPubMed
8.Corruccini, RS, Potter, RH (1980): Genetic analysis of occlusal variation in twins. Am J Orthod 78: 140154.Google Scholar
9.Corruccini, RS, Sharma, K, Potter, RHY (1986): Comparative genetic variance and heritability of dental occlusal variables in US and Northwest Indian twins. Am J Phys Anthrop 70: 293299.CrossRefGoogle ScholarPubMed
10.Corruccini, RS, Townsend, GC, Richards, LC, Brown, T (1990): Genetic and environmental determinants of dental occlusal variation in twins of different nationalities. Human Biology 62: 353367.Google ScholarPubMed
11.Daly, M, Wilson, M (1983): Sex, Evolution and Behaviour. 2nd ed. Belmont, CA Wordsworth.Google Scholar
12.Gaulin, SJC (1992): Evolution of sex differences in spatial ability. Yearbook of Physical Anthropology 35: 125151.Google Scholar
13.Horowitz, SD, Osborne, RH, DeGeorge, FVA (1960): A cephalometric study of cranio-facial variation in adult twins. Angle Orthod 30: 15.Google Scholar
14.Kang, KW, Christian, JC, Norton, JA (1978): Heritability estimates from twin studies. 1. Formulae of heretability estimates. Acta Genet Med Gemellol 27: 3944.Google Scholar
15.Kempthorne, O, Osborne, RH (1961): The interpretation of twin data. Am J Hum Genet 13: 320339.Google ScholarPubMed
16.Lancaster, JB (1991): A feminist and evolutionary biologist looks at women. Yearbook Phys Anthropol 34: 111.Google Scholar
17.Lundstrom, A (1984): Nature versus nurture in dento-facial variation. Eur J Orthod 6: 7791.Google Scholar
18.Lundstrom, A, McWilliam, JS (1987): A comparison of vertical and horizontal cephalometric variables with regard to heretability. Eur J Orthod 9: 104108.Google Scholar
19.Nakata, M, Yu, P, Davis, B, Nance, WE (1974): Genetic determinants of cranio-facial morphology: A twin study. Ann Hum Genet 37: 431443.Google Scholar
20.Osborne, RH, DeGeorge, FV (1959): Genetic Basis of Morphological Variation. Cambridge: Harvard University Press.Google Scholar
21.Potter, RHY, Yu, P, Christian, JC (1979): Association of twin zygosity with the mean and variance of tooth size. Acta Genet Med Gemellol 28: 211223.Google Scholar
22.Pucciarrelli, HM (1980): The effects of race, sex and nutrition on craniofacial differentiation in rats; A multivariate analysis. Am J Phys Anthropol 53: 359368.Google Scholar
23.Sharma, K (1987): Familial resemblance for craniofacial traits in a Punjabi population. Z Morph Anthrop 77: 157165.Google Scholar
24.Sharma, K, Corruccini, RS (1986): Genetic basis of dental occlusal variations in northwest Indian twins. Europ J Orthod 8: 9197.Google Scholar
25.Sharma, K, Corruccini, RS, Henderson, AM (1985): Genetic variance in dental dimensions of Punjabi twins. J Dent Res 64: 1389–91.Google Scholar
26.Sharma, K, Susanne, C (1991): Comparative genetic variance and heritability of head and facial traits in Northwest Indian and Belgian twins. Am J Hum Biol 3: 315324.Google Scholar
27.Susanne, C (1975): Genetic and environmental influences on morphological characteristics. Ann Hum Biol 2: 279287.Google Scholar
28.Susanne, S, Defrise-Gussenhoven, E, Wanseele, PV, Tassin, A (1983): Genetic and environmental factors in head and face measurements of Belgium twins. Acta Genet Med Gemellol 32: 229238.Google Scholar
29.Watnick, SS (1972): Inheritance of cranio-facial morphology. Angle Orthod 42: 339351.Google Scholar