(Tıp) Jenetik bir hastalıkta, bu hastalıkla malul bir ailenin veya neslin incelenmesine yol açan kişi (herediter bir hastalık serisinde rastlanılan ilk hasta)
The original individual, who because of their specific characteristic (e g extreme longevity) causes a study of other family members to determine if they have the same characteristic and if they have hereditary or genetic factors in common that could explain such a coincidence
– The person whose case serves as the stimulus for the study of other members of the family to identify the possible genetic factors involved in a given disease, condition, or characteristic