Question

Name a blood related autosomal Mendelian disorder. Why is it called Mendellian disorder? How is the disorder transmitted from parents to offspring?

Answer 1

Hint: According to the Mendelian’s Law different types of Mendellian disorders of inheritance are as follows: Autosomal dominant; Autosomal recessive; X-linked dominant; X- linked recessive; Mitochondrial. Eg- of Mendelian disorders in human: Sickle cell Anemia, thalassemia, Cystic fibrosis etc

Complete answer:
A blood related autosomal Mendelian disorder: Sickle Cell Anemia.
Due to mutation at a single gene locus Mendelian disorders occur due to which it gets transformed and not able to function normally. These transformed genes are then inherited by an offspring from their parents following the patterns of inheritance as described by Mendel.
As other Mendelian disorders, this disease follows the same pattern of inheritance. Hence, it is called Mendelian disorder.
In Sickle cell anemia, genes producing alpha haemoglobin chains get mutated, due to which at the sixth position of the amino acid chain, glutamine is substituted for valine. This results in the aggregation of haemoglobin molecules.
On one of the 22 autosomes, it is an autosomal linked disease which means this haemoglobin gene is present. If a parent has a mutation in one of the alleles of the haemoglobin gene, and the other is normal, they are considered as carriers. Hba Hbs parents will transfer this HBs allele to their offspring to transfer the disease.

Note:
At the time of formation of the gametes, the law of segregation of each gene gets separated so that every gamete will carry only one allele for each gene. Genetic disorders are a consequence of genome abnormality or mutations in a single gene.