The first "classical" twin study? Analysis of refractive error using monozygotic and dizygotic twins published in 1922.
The first classical twin studies, recognizing the potential of comparing findings in identical twins, have previously been reported to be those by Siemens and by Merriman, both published in 1924. However, we would like to bring to attention a study performed by Walter Jablonski, 2 years earlier (1922), investigating the contribution of heredity to refraction in human eyes. Jablonski examined the eyes of 52 twin pairs and by comparing the size of within-pair differences between identical and nonidentical twins was able to infer the heritability of a trait. Therefore, this is likely to be the first reported classical twin study.
Twin Research and Genetic Epidemiology Unit, St. Thomas' Hospital, London SE1 7EH, United Kingdom.
Shiao Hui M
SH
Liew
Hanno
H
Elsner
Tim D
TD
Spector
Christopher J
CJ
Hammond
D004200:Diseases in Twins / Q000235:genetics / Q000266:history*; D005260:Female; D049673:History, 20th Century; D006801:Humans; D008297:Male; D010641:Phenotype; D012030:Refractive Errors / Q000235:genetics / Q000266:history*; D018433:Twin Studies as Topic / Q000266:history*; D014429:Twins, Dizygotic / Q000235:genetics; D014430:Twins, Monozygotic / Q000235:genetics