Question

Why is it important to know how a trait, such as a genetic disorder, is passed and controlled?

Answer 1

It is very important to know about a genetic trait or genetic disorder that pass from generation to generation.To determine these type of situation we use many genetical tool such as Pedigree analysis, genetic mutation etc. In this era of modern science these type of technique use to determine that some disease or some character are fatal to progeny so that we can predict that the trait may pass or not pass to progeny due to which we prevent the progeny from that fatal trait or disorder.There are many of such examples ie. Erythroblastosis foetalis,Sickle cell anemia,Colourblindness,Baldness,Cancer etc.These type of genetic diseases & traits are fatal for the progeny.So by predicting them we save the progeny from these type of fatal disease some of them also fatal for the parent.Lets take the example of Erythroblastosis foetalis which is a case of Rh-incompatibility (mismatching) has been observed b/w the Rh -ve blood of a pregnant mother with Rh +ve blood of the foetus.Rh antigens of foetus do not get exposed to Rh -ve blood of mother in the first pregnancy as the two bloods are well seperated by the placenta.However during the delivery of first child,there is a possibility of exposure of maternal blood to small amounts of Rh +ve blood from the foetus.In such cases,the mother starts preparing antibodies against Rh antigen in her blood.In case of her subsequent pregnancies,the Rh antibodies from the mother (Rh -ve) can leak into blood of foetus (Rh +ve) & destroy the foetal RBCs.This could be fatal to foetus or could cause severe anaemia & jaundice to baby.This can be avoided by administering anti-Rh antibodies to mother immediately after the delivery of first child.So we understand that progeny can die due to severe symptoms,by the use of genetics we predetermine these type of conditions during the marriage b/c for this disease to occur condition should be Rh-ve female and Rh+ve male.So at the time of marriage proposal it should be reminding that this condition should not be follow up.Lets take another example of sickle cell anemia which is a autosomal recessive disorder,for passing to the progeny the mother should be carrier of this trait and father should be diseased.So it can also be prevented to pass in to progeny by examining its alleles especially of parents.Many of other genetic disorders can be check by examining the amniotic fluid during the pregnency so that it canbe decide that the baby which is born is normal for the family,society etc.B/c many of such disease are there in genetics in which only child not suffer but the family or society also suffer emotionally, psychologically due to social stigma.Example of such type of disorders are Down syndrome (trisomy of 21st chromosome),Cri-du-cat syndrome (deletion of short arm of 5th chromosome) the diseased child weeping like a kitten.