Sena syndrome (SS) is a rare, recessive, inherited condition.
SS is caused by a mutation in any one of several genes involved in mitochondrial translation.
In 80%80\%80% of people with SS, these mutations occur in nuclear DNA. In 20%20\%20% of people with SS, these mutations occur in mitochondrial DNA (mtDNA).
12%12\%12% of the nuclear DNA mutations that cause SS occur in the MRPS16 gene. A mutated MRPS16 gene codes for a shorter polypeptide than a non-mutated MRPS16 gene.
Name one type of MRPS16 gene mutation and explain how this mutation could lead to the production of a shorter polypeptide.
Globally, the frequency of SS is 1 in 50,000. In a specific isolated island group, the population is 54,000 and the frequency of SS is 1 in 1,600.
Estimate the number of people in this island group with SS caused by a mutation in the MRPS16 gene. Give your answer to the nearest whole number. Show your working.
The frequency of SS is higher in this island group than globally. Suggest and explain one reason why.
