Gemellology
Gemellology
a branch of biology and medicine dealing with the origin of twins (from one fertilized ovum or from different ova) and examining their resemblance and differences from the genetic, morphological, physiological, psychological, and pathological points of view. The so-called twin method, used mainly in the genetic study of man, makes it possible to study the effect on twins of hereditary factors and environmental conditions in the development of normal and pathological characteristics.