The Jaina Doctrine of Karma And The Science Of Genetics: ▪ Inheritance Of Physical Traits

The study of some evidence in Jaina works suggests that the development of each organ of body is regulated by a large number of genes (units of inheritance). The age at which a particular gene expresses itself phenotypically may vary widely as is suggested by ten dasas (stages) of human life.^[92]

The inheritance of mental ability or intelligence is one of the most important, yet one of the most difficult problems of human genetics as indicated by biology.^[93] The reference to the act in the Jaina works that the mental capacities of people form a continuous series from idiot (manda or jada) to genius (manīṣī). Suggests that intelligence is inherited by a system of polygenes. The term 'polygenic inheritance' or multiple factor inheritance is applied with two or more independent pairs in an addictive fashion i.e. skin colour in man^[94] brought about by karma.^[95] Other evidence substitute this hypothesis i.e. polygence and skin colour etc. cannot be separated into distinct alternate classes, and are not inherited by a single pair of genes.^[96] According to modern biology "the inheritance of feeble mindedness (maṁdata or jadata or balatva) is due to a single recessive gene.^[97]

It is now evident that the inheritance of mental defect is much more complex. Feeble mindedness may be caused by diseases^[98] or by other environment factors but "the majority of cases are due to inheritance.^[99] According to biology "special abilities musical, artistic, mechanical and mathematical have a hereditary basis and their inheritance is separate from that of general intelligence.^[100] Some of the phenomenas in human heritance have been observed by the Jainacāryās, some principles apply to the inheritance of human trait as are suggested by the study of Jaina biology and dasadaśās (ten stages of life).^[101] Most characteristics^[102] develop long before birth, but some, such as, hair and eye colour etc.^[103] may not appear until shortly after birth. Some such as amaurotic idiocy (balatva or mandatva)^[104] becomes evident in early childhood and still others, such as cough, phlegam, banding of the body, feeble sense organs etc.^[105] develop only after the individual has reached maturity.