chromosomal testing in humans essays

chromosomal testing in humans essays Chromosomal testing in humans, limitations and ethical implications In this credit assignment I have discussed the hot topic Chromosomal testing in humans. The limitations of the technology and its ethical implications and the present discussion going on is also discussed. The chromosomal basis of inheritance Mendel produced his results and hypothesis in 1866 in a journal, The Proceedings of the Brunn Natural History Society. At that time when it was sent to scientific societies all over the world, they all failed to comply with his theory because at that time they were all unable to relate the fact that hereditary factors could be transmitted from parents to offspring with the physical structures of the gametes, which they could observe. By 1900, due to the improvements in technology and advances in cytological techniques, the behaviour of chromosomes in the gametes and gametes were observed. Later two scientists Sutton and Boveri proposed that chromosomes were the carriers of Mendels factors, what we call today chromosome theory of heredity. This theory suggests that a pair of chromosomes carries each pair of factors with each chromosome carrying one of the factors. Johannsen later replaced the term factor, in 1909, with the term gene which is an alternative forms in which an allele may exist and occupy the same loci on homologous chromosomes. It is because of this development in the past that today we are able to carry out the so-called DNA testing and verify so many things. Now we know that hereditary characters are transmitted form parents to offspring through the genes in the gametes. In reproduction, the germ cells from the parents contain haploid chromosomes and upon reproduction the offspring is diploid. Chromosomes from the parents and the alleles in them determine the phenotypes of the offspring. In such a situation, the hereditarily carried diseases such as haemophilia a ...