1.Huntington Disease:
It is an autosomal dominant disease which it causes due to repetition mutation on the 4th chromosome. It occurs due to the repetition of codon (CAG). The dominant allele causes degenerative changes in the brain. This significantly affects the life expectancy; it is 20 year and the symptoms are observed. Some of the common symotoms are moodiness, fidgetiness, cognitive issues, personality shifts, depression, troubling in focusing and muscle twitching. Constant research is going on to cure but no vain yet.
2.Cystic Fibrosis
It is an autosomal recessive genetic disorder which is caused due to deletion mutation in 7th chromosome. This disease affects the epithelial cells. The normal CF gene codes for CRTR ( Cystic fibrosis transmembrane regulator protein) which transports the chloride ions across the membrane and water flows the ions to keep the epithelia smooth. However, when there is deletion of of the CTT gene which causes the formation of abnormal protein which causes the closing of the CFTR due to which the chloride ions can not go out. Some common symptoms are dryness since the sticky mucus builds up in the epithelia, secretion of digestive juices is interrupted in the pancreas. Also, mucus builds up in lungus too which can be fatal.
3.Colour Blindness:
It is a sex-linked ressive disorder and due to which it is more common in males as they have only one "X" choromosome. It gene of this is carried over the "X" chromosome. If the gene is present in male they are colour bling however since the allele is recessive heterozygous female are not colour blind.
