In $Huntington's$ chorea,limb movements are:

Sickle cell anemia and Huntington's chorea are both ..........

Given below are the two statements.
Statement $I$: Widow's peak is determined by an autosomal dominant gene.
Statement $II$: Heterozygous individuals have a straight hairline.
In the light of the above statements,choose the correct answer from the options given below:

What will be the genotypes of the parents of a colorblind daughter and a colorblind son?

Sickle cell anaemia is

Explain thalassemia.