A new disease is discovered in a monkey. It appears to be affecting a several genes in a localized area of cells in the animal.

When asked to make a hypothesis regarding the new disease, Rita and Zoe made the following statements.

Rita said that the disease is most likely the result of a somatic mutation because it is affecting several genes in a localized area of cells in the monkey.

Zoe said the disease is most likely the result of a germ-line mutation because it is several genes in a localized area of cells in the monkey.

Who’s has the best hypothesis for the cause of the new disease?

Rita
Zoe
Both are correct
Neither are correct

Mutation refers to any change in the nuceleotide sequence of the genetic material (DNA) caused by a mistake during DNA replication or induced by mutagens. Changes that occurs in genetic sequences can arise in an organism in two ways viz: somatic mutation or germline mutation

Somatic mutation is a kind of mutation that affects only the somatic (body) cells of that organism and hence, cannot be transferred to that organism's offsprings. When somatic mutation occurs, it only affects the same type of cells that mutated e.g if the genetic sequence of a liver cell mutates, only the cells of the liver will be affected.

On the other hand, germline mutation is the mutation that is passed down to an organism's offsprings because it occurred in the sex cells (gametes) of that organism. When germline mutation occurs, the entire cell of that organism is affected because that one mutated cell keeps on dividing.

According to the question, the disease appears to be affecting several genes in a localized area of the monkey's cells. "Localized" means a specific part. Hence, the mutation that led to the disease is most likely to be a somatic mutation since it is affecting only a specific area of the monkey's cells. Based on this, Rita's hypothesis is the best cause for the new disease in the monkey.