The human genome is split into 23 pair's chromosomes (DNA), which are coiled in a spiral ladder type through nucleotide hydrogen bases (cytosine-c, guanine-g, thymine-t, adenine-a) (fig1 below). Human cells have 46 chromosomes (fig 2 below) - 22 pairs of autosomes chromosomes 1 to 22 and two sex chromosomes X and y or X and X depending gender (sex-linked). Within these chromosomes are roughly 30,000 genes that controls and construct the organs in the body. There are over approximately 250 recognized sex-linked diseases, …showed first 75 words of 3505 total…

…showed last 75 words of 3505 total…Med Genet 38(1):80-4. 10.Van Deutekom JC, van Ommen GJ.(2003) Advances in Duchenne muscular dystrophy gene therapy. Nat Rev Genet. 4(10):774-83. 11.Zatz M, Sumita D, Campiotto S, Canovas M, Cerqueira A, Vainzof M, Passos-Bueno MR.(1998) Paternal inheritance or different mutations in maternally related patients occur in about 3% of Duchenne familial cases.Am J Med Genet. 78(4):361-5. Books Conner, M. , Smith, F. M. , (1997) Medical genetics ,5 :p77 . Blackwell science Sharper, S. P. (1993) Practical genetic counselling, 4:p 189 Butterworth-Heinemann