Met-Ile-Val-His-Tyr was the sequence of a hypothetical peptide. Assuming that there are two possible codons each for His, Val and Tyr, one possible…
Met-Ile-Val-His-Tyr was the sequence of a hypothetical peptide. Assuming that there are two possible codons each for His, Val and Tyr, one possible codon for Met, and four possible codons for Ile, the number of possible nucleotide sequences coding for this peptide would be
Select an option to attempt
Correct Answer: Option B
Explanation
X-linked recessive disorders affect hemizygous males (one X chromosome, one Y) much more frequently than heterozygous females (who are usually carriers). Key examples: Haemophilia A — X-linked recessive; caused by deficiency of clotting Factor VIII (F8 gene, Xq28). Haemophilia B (Christmas disease) — X-linked recessive; Factor IX deficiency (F9 gene, Xq27). Duchenne Muscular Dystrophy — X-linked recessive; dystrophin gene mutations (DMD gene, Xp21, largest human gene). Tay-Sachs disease — AUTOSOMAL recessive (chromosome 15, HEXA gene encoding β-hexosaminidase A subunit). Accumulation of GM2 ganglioside in neurons causes progressive neurodegeneration. Therefore Tay-Sachs does NOT show X-linked inheritance.