History and evolution of Genetics in the World and our country

ABSTRACT

In ancient times, our ancestors' imaginations about human reproduction and trait inheritance have mostly been of fabulous and superstitious nature. Beliefs of the philosophers of those days, including Greek philosophers, did not correspond with the principles of today's genetics in any way. The oldest scientific hypothesis in this regards is attributed to Hippocrates [460-370 B.C.], which denotes, in summary, that" man's water [semen] is an extract from the whole body containing all characteristics of the father, which is transferred to the child ". Aristotle [384-322 B.C.] believed that the semen originated from blood and gave life to the clotted menstrual blood after entering the uterus, producing a male fetus if the male force was stronger and a female fetus in case the female force was dominant. In general, they believed that all characteristics was inherited only from father, and the role of mother was just to nourish and nurture the fetus. This belief persisted for about 2000 years, until the time that William Harvey [1585 - 1675], the discoverer of blood circulation and a skilled hunter, showed that there were no traces of blood clots in the uterus of the pregnant hunted gazelles. After discovery of ovum by de Graaf in the second half of the seventeenth century, Malpigy proposed the preformation [ovist] theory. He believed that " inside the ovum, there is a miniature of a human being, which would start to grow and develop by entering of semen into the uterus. And after the discovery of spermatozoa by Hartsoeker and Van Ham Leeu Wenhock, this role was delegated to the spermatozoid. These contradictory and inappropriate beliefs were subject to discussions and disputes until the close of eighteenth century, when CE Wolf showed that the embryo is a product of fertilization of ovum with spermatozoid. It is interesting to know that in contrast to Greek philosophy and different western beliefs, the Sage Ferdowsi, Iranian great and famous poet, eight hundred years before Wolfs discovery [in the tenth century] as in description of the royal characteristics of Kaykhosrow, son of Siavash, grand son of Kaykavoos, and grand son of Afrasyab [from mother side] has describedthe equal participation of man and woman in development of fetus and inheritance of characteristics explicitly in exact accordance with scientific principles of today. And even more interesting is to know that in the Tabserat-el-avam, written in the first half of the thirteenth century, characteristics of the spermatozoid have been described in an appealing way and almost the same as what we know today. Furthermore, we have got interesting documents regarding origins and inheritance of some diseases from Mohammad Bin Zakaryaye Razi [great Iranian chemist, discoverer of alcohol], Buali Sina [Avicenna], and the sage Gorgani, which indicate their cognizance of the inheritance [genetics] fundamentals