Assume L410 is an acquired mutation that occurs only in hepatocytes of adults who were exposed to a certain mutagen. A woman with the L410 mutation has a child with an unaffected man. What is the probability that this child has the L410 mutation?

Question

Assume L410 is an acquired mutation that occurs only in hepatocytes of adults who were exposed to a certain mutagen.  A woman with the L410 mutation has a child with an unaffected man.  What is the probability that this child has the L410 mutation?

Quizplus · Accepted Answer

11ecba2d_0fe6_04fc_a3bf_21efb5c7a023_MD0008_00 All cells in the body can be classified as either germ (reproductive cells) or somatic (ie, the remaining cells). Germ cells are progenitor cells that undergo meiosis to produce gametes, such as sperm and oocytes. Germline mutations, which occur in the germ cells of parents, can be passed to offspring during sexual reproduction because parental gametic cells combine to form a zygote (fertilized egg). In contrast, parental somatic mutations, which involve alteration of somatic cell lineage (DNA) after conception, will not pass to an offspring because somatic cells are not directly involved in zygote formation. According to the question, the acquired mutation, L410, occurs only in the hepatocytes (liver cells) of adults due to exposure to a mutagen (agent causing genetic mutation). This means that the L410 mutation is somatic because it occurred sporadically in a minority of cells and not in the cells of the entire organism (as would be seen in germline mutations). It can be concluded that L410 occurred during the lifetime of the individual and not in the gametes of his or her parents. Therefore, the somatic L410 mutation in the mother will not be inherited by the offspring, and the probability of this woman and a genetically normal man having a child with the L410 mutation is equal to zero (Choices B, C, and D). Educational objective: Mutations that occur in the reproductive cells of parents are called germline mutations. These mutations can be passed from parent to offspring, and result in the offspring carrying the mutation in all of its cells. Parental somatic mutations, which occur in non-sex cell lineages during an organisms' lifetime, are not inherited by the offspring.

Assume L410 Is an Acquired Mutation That Occurs Only in Hepatocytes