Concept explainers
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?
With such a complex genetic condition that may also depend on environmental factors, is there a way to calculate the risk that our next child will be autistic?
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Essentials of Genetics (9th Edition) - Standalone book
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- What is the role of imprinting in human genetic disorders? \ Select the two correct answers. Imprinting defects cause myelodysplastic syndrome. Imprinting is a process that leads to human genetic disorders. Imprinting defects cause Prader-Willi syndrome, Angelman syndrome, Beckwith-Wiedemann syndrome, and several others. When mutations occur in imprinted genes, heritable changes in gene activity may occur. Imprinting is a process that cures human genetic disorders. When mutations occur in imprinted genes, only non- heritable changes in gene activity may occur.arrow_forward1. What role does a patient's genetics have in their symptoms of muscular dystrophy? What causes various mutations to cause distinct symptoms? (two to three sentences) (Think about why various mutations in different genes cause different illnesses.)2. What can family history teach you about a patient's muscular dystrophy inheritance and, hence, genetic basis? (two to three sentences)3. The X-chromosome contains the mutation that causes Duchenne Muscular Dystrophy (DMD). Explains how this impacts DMD inheritance and why DMD patients are disproportionately male. (two to three sentences)arrow_forwardTalk about the challenges involved in determining the genetic components of polygenic illnesses. Explain complementation groups and how the biochemical underpinnings of disease are determined using them. Hereditary illnesses of genomic instability include Werner syndrome, Bloom syndrome, XP, ataxia-telangiectasia, and Fanconi anemia. Which of these ailments has molecular mechanisms behind it? Which kind of genetic instability is connected to which disorder?.arrow_forward
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- Name three genes whose mutations lead to an altered behavioral phenotype. Briefly describe the normal function of the mutated gene as well as the altered phenotype.arrow_forwardLO74 Explain how epigenetic markers are inherited. How do epigenetic marks compare in monozygotic twins? They stay the same throughout their lives because monozygotic twins are genetically identical. They are similar early in life but are increasingly dissimilar with age. DNA methylation patterns are similar, but histone acetylation patterns are very different. They are different at birth, but a similar environment during childhood causes them to become more similar with time.arrow_forwardQuestion: The disorder: Red-Green color blindness Explain the mode of inheritance of the disorder (recessive, dominant, x-linked, etc.) . Can a person be a carrier of this disorder? • Describe the probability of having a child with the disorder -- give a specific scenario (ex. both parents are heterozygous for the trait) • Describe the symptoms associated with this disorder Explain the prognosis of a person born with this disorderarrow_forward
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