Describe Mendelian Disorder.
Describe Mendelian Disorder.
Mendelian disorders are mainly determined by alternation or mutation in the single gene.
These disorders are transmitted to the offspring on the same lines as the principle of inheritance
The pattern of inheritance of Mendelian disorders can be traced in a family by the pedigree analysis.
Most common and prevalent Mendelian disorders can be traced in a family by the pedigree analysis.
Most common and prevalent Mendelian disorder are Haemophilia, Cystic fibroses, Sickle cell anaemia, Colour blindness, Phenylketonuria, Thalassemia etc.
Such Mendelian disorder may be dominant or recessive.
By pedigree analysis one can easily understand whether the trait in question is dominant or recessive.
Similarly the trait may also be linked to the sex chromosome as in case of haemophilia.
It is evident that this $X$-linked recessive trait shows transmission from carrier female to male progeny.
A representative pedigree is shown in figure for dominant and recessive traits.
Colour blindness is sex linked recessive disorder due to defect in either red or green cone of eye resulting in failure to discriminate between red and green colour.
Similar Questions
If a colour blind man marries a woman who is homozygous for normal vision, the probability of their son being colour blind is .........
If a colour blind man marries a woman who is homozygous for normal vision, the probability of their son being colour blind is .........
A man whose father was colour blind marries a woman who had a colour blind mother and normal father. What percentage of male children of this couple will be colour blind?
A man whose father was colour blind marries a woman who had a colour blind mother and normal father. What percentage of male children of this couple will be colour blind?
- [NEET 2014]
Why is the frequency of red-green colour blindness is many times higher in males than that in the females ?
Why is the frequency of red-green colour blindness is many times higher in males than that in the females ?
Pattern baldness, moustaches and beard in human males are examples of
Pattern baldness, moustaches and beard in human males are examples of
- [AIPMT 2003]
A girl of normal vision whose father was colourblind marries a man of normal vision whose father was also colourblind. Their sons would be (of total number of $sons$)
A girl of normal vision whose father was colourblind marries a man of normal vision whose father was also colourblind. Their sons would be (of total number of $sons$)