How traits are transferred from parents to next generation? Some thoughts are fact and some are based on imagination. Science is always changing. It is therefore necessary to warnabout such false concepts and indicate the actual facts involved.
1- Blood as a hereditary force
Blood plays very important role in transmission of traits. It is thought that blood relatives have some background of genetics. But problem with blood is environment; if someone gets diseased blood then he will become patient. People refuse blood transfusion from a member of another race due to fear that they will acquire characters of that race. Actually it is far from being true.
2- Telegony (Ti-leg-e.ni)
According to this false thought effects of male parent remains constant in all offspring of female generations after generations to which he has been copulated. For instance a white woman married to a Negro man and gives birth to a mulatto. Woman divorced and marries a white man, their child has Negro blood.Lord Morton of England first time reported a case of Telegony about 150 years ago. He crossed a young Arabian (chestnut mare) with Quagga (a zebra like horse with distinct strips on the body), a filly young mare with strip on the leg and weaken ridges between shoulder bones.
Later this mare was copulated with pure blooded Arabian Stallion and produced a filly and colt on two consecutivecopulating. These offspring characteristicallypresented Arabian characters as was expected, but there seems to be faint strips on the neck and weakens in certain other characters the offspring appeared to look like the Quagga. It was acknowledged for some time but later on it was not proved true. Now day’s knowledge about reproductive cells totally rules out anylikelihood of this concept.
3- Influence of the age of the parents
Immature and too old parents produce defective offspring. Children of immature parents are inferior in hereditary qualities as compared to the children of mature parents. There is evidence that a five years old mother give birth to a baby grown into a child who is fully developed mentally and physically. Children of old parents have poor vigor. In old age degenerative changes occurs in body organs but not in cells. These changes are due to environmental effects. In Texas many quality bull has been discarded due to this false concept and resulted in the loss of certain hereditary qualities which may not appear again in future generation of cattle.
4- Influence of drugs
Addicted parents produce defective children; yes it is true but not in terms of genetics due to fact that environment plays its role. Addiction is a kid of change of environment.A drinking mother may bear an embryo she is carrying, since alcohol can pass through blood of fetus and child may have symptoms of alcoholism but it is an environmental effect.
5- Influence of acquired characters
Most important false concept about heredity is that characters acquired by the parents during their life time may influence the offspring i.e. inheritance of acquired characters, idea given by Lamarck. Resurgence of Lamarckism occurs in 1930s when T. D. Lysenko, a young plant breeder from Ukraine, give the idea that efficiency of the plant development could be improved by manipulating environmental conditions. He believed that such improvements would be incorporated into the genetic material and hence can be passed into future generations of plants. This idea supports the inheritance of acquired characters but now days we know that this is totally wrong.
6- Maternal Impressions
Eager mother may ‘mark’ or impact the development of her child during pregnancy. For instance; if a lady daily visits strawberry her offspring could has a strawberry-shaped birth mark on his/her body. Geneticists opposed it. As let if it is true such type of birth mark also appears in regions where mother have never visited strawberries.
These misconceptions are due the result of heredity or environment but heredity plays role in transmission of genes while environment decides gene expression which in turn shows certain character.I hope that this article will help the readers understanding genetic basis of heredity in a better way who are interested to know about their selves.