Chapter 7, Problem 1CS

CASE STUDY | Links to autism

As parents of an autistic child, a couple decided that entering a research study would not only educate them about their son's condition, but also help further research into this complex, behaviorally defined disorder. In an interview, researchers explained to the parents that autism results from the action of hundreds of genes and that no single gene accounts for more than a small percentage of cases. Recent studies have identified 18 genes that have a higher likelihood of involvement, referred to as candidate genes; three of these, on chromosomes 2, 7, and 14, are regarded as very strong candidate genes. Generally unaware of the principles of basic genetics, the couple asked a number of interesting questions. If you were the interviewer, how would you respond to them?

How might identification of a “candidate” gene be helpful in treating autism?

Summary Introduction

To analyze:

The query of the parents of an autistic child, about the risk of having second child autistic, as the genetic condition depends on several factors.

Introduction:

Autism is the disease that is a result of the action of hundreds of genes. Almost 18 genes are known to be most likely involved in it, that are referred to as “candidate” gene. Out of 18 genes, three genes are present on chromosome number 2, 7, and 14, which are regarded as a strong candidate gene.

Explanation of Solution

Autism is a neurodevelopmental disorder that affects the individual’s ability to interact with people. It occurs at very early stage in childhood. Autism has a genetic basis, even though the genetics of the autism is complex.

Selection of candidate gene can be helpful in treating the autism. The researchers can locate the gene and can isolate the mutation. The treatment regimens can be developed by the researchers to treat the mutation, by targeting those specific mutations. Gene knockout and gene knock-in can be used through either the mutated genes are deleted from the organism or in place of the defected gene new gene is inserted, for its normal function.

Neuroligin 3 is a cell adhesion protein that functions to connect the brain cells to each other. Mutation in the neuroligin 3, that leads to the change in 451 amino acid from arginine to cystine. It is the genetic change associated with autism. This change can be corrected by targeting the gene and so the identification of the gene can be helpful in treating the autism.

As this genetic disorder is controlled by a number of genes, researchers suggest that there is a higher probability of autism in second child also, as the siblings share similarity with respect to their genetic structure.

Conclusion

Therefore, it can be concluded that identification of the candidate gene can be helpful in treating the autism, and there is a higher probability of autism in second child if the first one is autistic.