Describe Mendelian disorders.

(N/A) Mendelian disorders are primarily determined by alterations or mutations in a single gene. These disorders are transmitted to the offspring following the same principles of inheritance as studied in Mendelian genetics.
The pattern of inheritance of such Mendelian disorders can be traced in a family through pedigree analysis.
Some common and prevalent Mendelian disorders include Haemophilia,Cystic fibrosis,Sickle-cell anaemia,Colour blindness,Phenylketonuria,and Thalassemia. It is important to note that these Mendelian disorders may be dominant or recessive.
Through pedigree analysis,one can easily determine whether the trait in question is dominant or recessive. Similarly,the trait may also be linked to a sex chromosome,as seen in the case of haemophilia.
It is evident that an $X$-linked recessive trait shows transmission from a carrier female to male progeny. Representative pedigrees for dominant and recessive traits are shown in the figure.