Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-25T02:32:41.660Z Has data issue: false hasContentIssue false

Iatrogenic Influences on the Heritability of Childhood Tonsillectomy: Cohort Differences in Twin Concordance

Published online by Cambridge University Press:  01 August 2014

N.G. Martin*
Affiliation:
Queensland Institute of Medical Research, Bramston Terrace, Brisbane, Australia
U. Kehren
Affiliation:
Queensland Institute of Medical Research, Bramston Terrace, Brisbane, Australia
D. Battistutta
Affiliation:
Queensland Institute of Medical Research, Bramston Terrace, Brisbane, Australia
J.D. Mathews
Affiliation:
Menzies School of Health Research, Darwin, Australia
*
Queensland Institute of Medical Research, Bramston Terrace, Herston QLD 4006, Australia

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.

In 1980-82, a mailed questionnaire was completed by 3,810 pairs of adult twins enrolled on the Australian NH&MRC Twin Register. Twins were asked whether they had had their tonsils out and, if so, at what age. The sample was divided into four birth cohorts of approximately equal size, and only childhood tonsillectomy (to the age of 18) was considered. The prevalence of tonsillectomy differed markedly between cohorts, being highest in those born in the 1940s and early 1950s. Within each cohort, the prevalence was very similar in MZ and DZ twins, yet concordance was much higher in MZ twins, indicating the importance of genetic factors in predisposition to tonsillectomy. However, the proportions of variance in liability due to genetic and shared environmental factors differed markedly between cohorts. In the 1950s, when tonsillectomy was fashionable, shared environment accounted for 60% of variance and genetic factors for only 29%. However, by the early 1960s, when tonsillectomy was going out of fashion, heritability was up to 0.82 and shared environment accounted for only 10% of variance. Our results illustrate, once again, that heritability is not a constant, but depends on the precise characteristics of the population and the time at which it is studied.

Type
Research Article
Copyright
Copyright © The International Society for Twin Studies 1991

References

REFERENCES

1.Brook, I (1987): The clinical microbiology of Waldeyer's ring. Otolaryngol Clin North Am 20: 259–72.CrossRefGoogle ScholarPubMed
2.Clark, P, Jardine, R, Jones, P, Martin, NG, Walsh, RJ (1981): Directional dominance for low IgM and IgA levels. Am J Hum Genet 33: 709–21.Google ScholarPubMed
3.Duffy, DL, Martin, NG, Mathews, JD (1990): Appendectomy in Australian twins. Am J Hum Genet 47: 590592.Google ScholarPubMed
4.Falconer, DS (1965): The inheritance of liability to certain diseases estimated from the incidence among relatives. Ann Hum Genet 29: 5176.CrossRefGoogle Scholar
5.Freeman, JL, Jekel, JF, Freeman, DH (1982): Changes in age and sex specific tonsillectomy rates: United States, 1970-1977. Am J Pub Health 72: 488–90.CrossRefGoogle ScholarPubMed
6.Heath, AC, Berg, K, Eaves, LJ, Solaas, MH, Corey, LA, Sundet, J, Magnus, P, Nance, WE (1985): Education policy and the heritability of educational attainment. Nature 314: 734–6.CrossRefGoogle ScholarPubMed
7.Heath, AC, Neale, MC, Hewitt, JK, Eaves, LJ, Fulker, DW (1989): Testing structural equation models for twin data using LISREL. Behav Genet 19: 935.Google Scholar
8.Jöreskog, KG, Sörbom, D (1986): PRELIS. A Program for Multivariate Data Screening and Data Summarisation. A Preprocessor for LISREL. Mooresville, Indiana: Scientific Software Inc.Google Scholar
9.Jöreskog, KG, Sörbom, D (1989): LISREL 7. A Guide to the Program and Applications (2nd Ed). Chicago: SPSS Inc.Google Scholar
10.Kornblut, AD (1987): A traditional approach to surgery of the tonsils and adenoids. Otolaryngol Clin North Am 20: 349–61.CrossRefGoogle ScholarPubMed
11.Learoyd, B (1985): “Discretionary” surgery statistics. Med J Aust 142:528.Google Scholar
12.Neale, MC, Eaves, LJ, Hewitt, JK, MacLean, CJ, Meyer, JM, Kendler, KS (1989): Analyzing the relationship between age at onset and risk to relatives. Am J Hum Genet 45: 226239.Google ScholarPubMed
13.Richtsmeier, WJ, Shikani, AH (1987): The physiology and immunology of the pharyngeal lymphoid tissue. Otolaryngol Clin North Am 20: 219–28.Google Scholar
14.Treloar, SA, Martin, NG (1990): Age at menarche as a fitness trait: nonadditive genetic variance detected in a large twin sample. Am J Hum Genet 47: 137148.Google Scholar
15.Wilson, JMG (1981): Adenotonsillectomy: Scotland is beating England and Wales. Lancet i:895–90.CrossRefGoogle Scholar