Its no accident that off-spring resemble their parents. Deoxyribonucleic acid or DNA, located within each cell nucleus is a special chemical, that determines our genetic inheritance in a very orderly way. Under the microscope DNA looks like a mass of tangled threads which consist of tiny subunits called genes. Genes carry instructions, sometimes called the blueprint of life, for various characters like hair color, height, eye color. Our genes are received from both mother and father, half from each. Genes instruct our bodies to make proteins - which determines the shape and function of each cell. Each gene controls the production of a particular protein. Genes produce millions of different proteins through different arrangements of just four simple molecules the nucleotides - adenine (A), cytosine (C), thymine (T), and guanine (G). These A,C,T and G's are like letters of the alphabet - their order "spells" out the language of life.
The Human Genome Project (HGP) was proposed in the 1980s and was formally initiated in 1990. Its major aims are to map and determine the chemical sequences of the three billion nucleotide base pairs that comprise the human genome. Completion of the HGP in the projected 15 years will provide a source book for biology and medicine. The Human Genome Diversity Project (HGDP) complements the HGP by examining the genomic variation of the human species, through analysis of DNA from populations, families and individuals worldwide.
There are many different techniques involved in gene screening. With the start of the Human Genome Mapping Project some of these techniques have been altered to speed up the screening process. Examples of these techniques include PCR (polymerize chain reaction), RFLP's (restricti...
... middle of paper ...
2. Encyclopaedia Britannica. Obtained from WWW : http://search.eb.com/bol/search?Dbase=Ar
3. Genetic Screening and Counseling. Obtained from WWW : http://www.gaucher.org.uk/genetic.htm
4. Genetic Screening and Ethics an Overview Obtained from WWW : http://www.woodrow.org/teachers/bi/1992/gen_screen1.html
5. Genetic Testing and Genetic Screening. Obtained from WWW : http://www.georgetown.edu/research/nrcbl/scopenotes/sn22.htm
6. The Application of Human Genetic Research. Obtained from WWW : http://www.bioportfolio.com/efb3.htm#hgp
7. Marshall, Eliot. 1999. Beryllium Screening Raises Ethical Issues. Science. 285(5425): pp178-179.
8. Blatt, Robin JR."An Overview of genetic screening and diagnostic Tests in Health Care". Obtained from the WWW: http://www.geneletter.org/0996/screening.htm