Genetics and RNA: Types and Disorders

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which type of RNA is directly involved in the process of translation?

  • tRNA (correct)
  • DNA
  • rRNA
  • mRNA

What is the primary genetic cause of Down Syndrome?

  • Absence of a chromosome pair
  • A single X chromosome
  • An extra X chromosome
  • Trisomy 21 (correct)

Which of the following is a common symptom of Turner Syndrome?

  • Small testes
  • Gynecomastia
  • Protruding tongue
  • Webbed neck (correct)

What is the most typical chromosomal cause of Klinefelter Syndrome?

<p>47,XXY (A)</p> Signup and view all the answers

A disease that appears in children, but not their parents, is most likely what form of trait inheritance?

<p>Autosomal recessive (A)</p> Signup and view all the answers

If one parent is affected by an autosomal dominant disease, what is the probability that their child will inherit the condition?

<p>50% (A)</p> Signup and view all the answers

According to the content, how does the ALDH2*2 gene affect the likelihood of alcoholism?

<p>It lowers the likelihood of developing alcoholism. (B)</p> Signup and view all the answers

What percentage of risk for bipolar disorder is estimated to be due to genetic factors, according to the provided text?

<p>60% (A)</p> Signup and view all the answers

Suppose a novel RNA molecule is discovered whose primary function is to carry genetic information from DNA to the ribosome. Which of the known RNA types is most analogous to this newly discovered molecule?

<p>Messenger RNA (mRNA) (A)</p> Signup and view all the answers

A child presents with a constellation of symptoms including a low nasal bridge, epicanthal folds, and poor muscle tone. Genetic testing reveals an extra copy of chromosome 21. Which of the follow conditions best describes these findings?

<p>Down Syndrome (A)</p> Signup and view all the answers

A female patient exhibits short stature, a webbed neck, and is infertile. Which of the following chromosomal patterns is most likely indicated?

<p>45, X (D)</p> Signup and view all the answers

A male patient presents with gynecomastia, small testes, and sparse body hair. Karyotype analysis reveals an extra X chromosome (47,XXY). This chromosomal abnormality is most commonly associated with which of the following?

<p>Increased maternal age (D)</p> Signup and view all the answers

Considering autosomal dominant inheritance, what is the chance that an offspring will inherit a condition if one parent is affected and heterozygous for the trait while the other is unaffected?

<p>50% (B)</p> Signup and view all the answers

In an autosomal recessive disorder, if both parents are carriers for a trait, what is the probability of an offspring from those parents expressing the condition?

<p>25% (D)</p> Signup and view all the answers

How does the ALDH2*2 gene allele affect a person's risk of developing alcoholism, compared to other alleles?

<p>Decreases the risk significantly (D)</p> Signup and view all the answers

What is the percentage risk if a first-degree relative is diagnosed with bipolar disorder?

<p>5-10% (B)</p> Signup and view all the answers

According to the provided content, which statement best describes the genetic contribution to risk in the context of bipolar disorder and major depressive disorder?

<p>The genetic contribution to the risk of bipolar disorder is approximately double that of major depressive disorder. (A)</p> Signup and view all the answers

A child with an autosomal recessive disorder is born to parents who do not express the symptoms of the disorder. If this child were to have offspring with an unaffected non-carrier partner, which of the following is most likely?

<p>Half of the offspring will be unaffected carriers. (C)</p> Signup and view all the answers

Signup and view all the answers

Flashcards

Messenger RNA (mRNA)

Molecule responsible for carrying genetic information from DNA to ribosomes, where protein synthesis occurs.

Transfer RNA (tRNA)

A type of RNA that helps decode mRNA during protein synthesis by bringing the correct amino acids to the ribosome.

Ribosomal RNA (rRNA)

A type of RNA that forms part of the ribosome, the cellular machinery responsible for protein synthesis.

Down Syndrome

A genetic disorder caused by an extra copy of chromosome 21. Symptoms include mental challenges, distinctive facial features, and health issues.

Signup and view all the flashcards

Turner Syndrome

A genetic disorder affecting females, caused by a single X chromosome. Symptoms include short stature, webbed neck, and infertility.

Signup and view all the flashcards

Klinefelter Syndrome

A genetic disorder affecting males, caused by an extra X chromosome. Symptoms include male appearance, breast development, and smaller testes.

Signup and view all the flashcards

Autosomal Dominant Inheritance

A pattern of inheritance where a single copy of the mutated gene is enough to cause the disease.

Signup and view all the flashcards

Autosomal Recessive Inheritance

A pattern of inheritance where two copies of the mutated gene are needed to cause the disease.

Signup and view all the flashcards

What is the cause of Down Syndrome?

An extra copy of chromosome 21, leading to specific physical characteristics and developmental challenges.

Signup and view all the flashcards

What is Turner Syndrome?

A condition where a female only has one X chromosome, resulting in short stature, webbed neck, and infertility.

Signup and view all the flashcards

What is Klinefelter Syndrome?

A genetic disorder where males have an extra X chromosome, leading to specific physical characteristics and potential health complications.

Signup and view all the flashcards

What is Autosomal Dominant Inheritance?

A pattern of inheritance where a mutated gene from one parent is enough to cause the disease.

Signup and view all the flashcards

What is Autosomal Recessive Inheritance?

A pattern of inheritance where two copies of the mutated gene are needed to cause the disease.

Signup and view all the flashcards

What is the role of the ALDH2*2 gene?

A gene variation associated with reduced risk of alcohol dependence, making individuals less likely to become alcoholics.

Signup and view all the flashcards

What is the role of the GABA gene variation?

A gene variation associated with increased risk of Bipolar Affective Disorder (Manic Depressive Disorder).

Signup and view all the flashcards

Study Notes

Types of RNA

  • Messenger RNA (mRNA), Transfer RNA (tRNA), and Ribosomal RNA (rRNA) facilitate protein synthesis.
  • Transcription (DNA to mRNA) and translation (mRNA to proteins)

Genetic Disorders

Down Syndrome

  • Cause: Trisomy 21 (extra chromosome 21).
  • Symptoms: Intellectual challenges, low nasal bridge, epicanthal folds, protruding tongue, short stature, hypotonia (poor muscle tone).
  • Associated Conditions: Congenital heart disease, respiratory infections, Alzheimer's disease, leukemia.

Turner Syndrome

  • Cause: Single X chromosome (45,X).
  • Symptoms: Short stature, webbed neck, widely spaced nipples, absence of ovaries (sterility).
  • Treatment: Estrogen therapy during adolescence.

Klinefelter Syndrome

  • Cause: Extra X chromosome(s) (e.g., 47,XXY).
  • Symptoms: Male appearance, gynecomastia, small testes, sparse body hair.
  • Associated with increased maternal age.

Inheritance Patterns

Autosomal Dominant Inheritance

  • Characteristics:
    • Rare disease
    • Equal affect on males and females
    • Equal likelihood of inheritance for males and females
    • No skipping of generations
    • 50% chance of inheriting the condition if one parent is affected (heterozygous).
    • 50% chance of occurrence/ recurrence of disease in offspring (if one parent is affected and the other is not) for each child.
    • Disease expression may vary in severity.
  • Associated Conditions: Huntington's disease, Marfan syndrome.

Autosomal Recessive Inheritance

  • Characteristics:
    • Appears in children, not parents.
    • 25% chance of offspring from two carrier parents being affected.
    • One-quarter of offspring normal, one-half will be carriers.
  • Implications: Offspring of non-alcoholic parents, raised by alcoholic parents, did not have increased risk.

Genetic Factors in Alcoholism and Mental Illness

  • Alcoholism:

    • ALDH2*2 allele: Associated with a decreased likelihood of alcoholism.
    • GABA allelic variation: Associated with an increased risk of alcoholism.
  • Bipolar Disorder (Manic Depressive Disorder):

    • Genetic risk: 60%
    • Family studies: First-degree relative: ~5–10% increased risk compared to general population.
    • Twin and family studies suggest 60% of bipolar risk is due to genetic factors; 30% of major depressive disorder risk is due to genetics.
  • Schizophrenia:

    • Genetic risk: Heterogeneous; numerous genetic and environmental factors are involved.
    • Increased Risk Due to Family history
      • One affected parent: 10 times higher risk compared to the general population.
      • One affected sibling and parent: Increased risk of 20%.
      • Two affected parents: ~50% risk.
  • Implicated Genes: Brain-expressed genes whose products interact with glutamate receptors.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

More Like This

Use Quizgecko on...
Browser
Browser