
Concept explainers
Why do you think it has been so difficult to identify genes underlying schizophrenia?
Rachel asked to see a genetic counselor because she was concerned about developing schizophrenia. Her mother and maternal grandmother both had schizophrenia and were institutionalized for most of their adult lives. Rachel’s three maternal aunts are all in their 60s and have not shown any signs of this disease. Rachel’s father is alive and healthy, and his family history does not suggest any behavioral or genetic conditions. The genetic counselor discussed the multifactorial nature of schizophrenia and explained that many candidate genes have been identified that may be mutated in individuals with the condition. However, a genetic test is not available for presymptomatic testing. The counselor explained that based on Rachel’s family history and her relatedness to individuals who have schizophrenia, her risk of developing it is approximately 13%. If an altered gene is in the family and her mother carries the gene, Rachel has a 50% chance of inheriting it.

To describe: The difficulties to identify genes underlying schizophrenia.
Introduction: Schizophrenia is characterized by thought disorders, delusions, and anti-social behavior. This is much common in children and at least lasts for 6 months. Schizophrenia is found within a region of DNA located on chromosome 6. The genes underlying the disease are still unknown.
Explanation of Solution
Schizophrenia is a behavioral disorder that causes widespread human suffering. Several genetic studies have shown that hundreds of genes are linked to schizophrenia. Each gene contributes a small part to the risk of developing the disease.
Therefore, a mutation in a gene does not confirm the presence of schizophrenia. Similarly, if someone has schizophrenia with a mutation in a gene also does not mean that this mutation is responsible for the behavior of the respective person.
Hence, it is difficult to find genetic determinants underlying schizophrenia.
Want to see more full solutions like this?
Chapter 18 Solutions
Human Heredity: Principles and Issues (MindTap Course List)
- "One of the symmetry breaking events in mouse gastrulation requires the amplification of Nodal on the side of the embryo opposite to the Anterior Visceral Endoderm (AVE). Describe one way by which Nodal gets amplified in this region." My understanding of this is that there are a few ways nodal is amplified though I'm not sure if this is specifically occurs on the opposite side of the AVE. 1. pronodal cleaved by protease -> active nodal 2. Nodal -> BMP4 -> Wnt-> nodal 3. Nodal-> Nodal, Fox1 binding site 4. BMP4 on outside-> nodal Are all of these occuring opposite to AVE?arrow_forwardIf four babies are born on a given day What is the chance all four will be girls? Use genetics lawsarrow_forwardExplain each punnet square results (genotypes and probabilities)arrow_forward
- Give the terminal regression line equation and R or R2 value: Give the x axis (name and units, if any) of the terminal line: Give the y axis (name and units, if any) of the terminal line: Give the first residual regression line equation and R or R2 value: Give the x axis (name and units, if any) of the first residual line : Give the y axis (name and units, if any) of the first residual line: Give the second residual regression line equation and R or R2 value: Give the x axis (name and units, if any) of the second residual line: Give the y axis (name and units, if any) of the second residual line: a) B1 Solution b) B2 c)hybrid rate constant (λ1) d)hybrid rate constant (λ2) e) ka f) t1/2,absorb g) t1/2, dist h) t1/2, elim i)apparent central compartment volume (V1,app) j) total AUC (short cut method) k) apparent volume of distribution based on AUC (VAUC,app) l)apparent clearance (CLapp) m) absolute bioavailability of oral route (need AUCiv…arrow_forwardYou inject morpholino oligonucleotides that inhibit the translation of follistatin, chordin, and noggin (FCN) at the 1 cell stage of a frog embryo. What is the effect on neurulation in the resulting embryo? Propose an experiment that would rescue an embryo injected with FCN morpholinos.arrow_forwardParticipants will be asked to create a meme regarding a topic relevant to the department of Geography, Geomatics, and Environmental Studies. Prompt: Using an online art style of your choice, please make a meme related to the study of Geography, Environment, or Geomatics.arrow_forward
- Plekhg5 functions in bottle cell formation, and Shroom3 functions in neural plate closure, yet the phenotype of injecting mRNA of each into the animal pole of a fertilized egg is very similar. What is the phenotype, and why is the phenotype so similar? Is the phenotype going to be that there is a disruption of the formation of the neural tube for both of these because bottle cell formation is necessary for the neural plate to fold in forming the neural tube and Shroom3 is further needed to close the neural plate? So since both Plekhg5 and Shroom3 are used in forming the neural tube, injecting the mRNA will just lead to neural tube deformity?arrow_forwardWhat are some medical issues or health trends that may have a direct link to the idea of keeping fat out of diets?arrow_forwardwhat did charles darwin do in sciencearrow_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage LearningBiology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning
- Biology Today and Tomorrow without Physiology (Mi...BiologyISBN:9781305117396Author:Cecie Starr, Christine Evers, Lisa StarrPublisher:Cengage Learning



