Genetic Disorders: Marfan and Albinism

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Questions and Answers

What does the term 'Albinism' derive from?

A Greek word for light

A Latin word meaning white (correct)

A French term for absence

An Arabic phrase for clarity

Which of the following tissues are most affected by Albinism?

Nervous tissues

Connective tissues

Ectoderm-derived tissues (correct)

Muscle and bone

What is a major characteristic of Albinism?

Abnormal skin growths

Diminished or absent melanin (correct)

Excess melanin production

Increased skin elasticity

What is the main cause of the decreased skin pigmentation in Albinism?

Genetic mutations affecting melanin production Signup and view all the answers

What is the inheritance pattern of Marfan syndrome?

Autosomal dominant Signup and view all the answers

Which feature is typically NOT associated with Albinism?

Increased melanin production Signup and view all the answers

In which part of the body is melanin primarily absent due to Albinism?

Ectoderm-derived tissues Signup and view all the answers

What percentage of Marfan syndrome cases are attributable to de novo mutations?

25% Signup and view all the answers

How does Albinism primarily affect an individual's appearance?

Leads to pale skin and light hair Signup and view all the answers

On which chromosome is the FBN1 gene, associated with Marfan syndrome, located?

Chromosome 15 Signup and view all the answers

What is the role of fibrillin in connective tissues?

Maintains elasticity and stability Signup and view all the answers

What can be a significant health concern for individuals with Albinism?

Heightened sensitivity to sunlight Signup and view all the answers

What is a major risk regarding the aorta in individuals with Marfan syndrome?

Aortic dissection Signup and view all the answers

What are microfibrils primarily responsible for?

Strength and stability in tissues under stress Signup and view all the answers

How common is Marfan syndrome in the general population?

1 in 3000 to 5000 Signup and view all the answers

Which of the following best describes the consequences of a loss of function in the FBN1 gene?

Deficiency or non-production of fibrillin Signup and view all the answers

What percentage of global albinism cases is attributed to OCA2?

30% Signup and view all the answers

Which gene mutation is associated with OCA1?

TYR Signup and view all the answers

What type of inheritance pattern is observed in Oculocutaneous Albinism (OCA)?

Autosomal recessive Signup and view all the answers

What is the primary role of the OCA2 gene in albinism?

Acts as a transport system Signup and view all the answers

What is the chance of a child having albinism if both parents are carriers of the gene?

1 in 4 Signup and view all the answers

Which type of albinism is most common in Puerto Rico?

HPS Signup and view all the answers

Which gene mutation is linked to OCA4?

SLC45A2 Signup and view all the answers

What type of mutation is characterized by the loss of one or more nucleotides?

Deletion Signup and view all the answers

In X-linked inheritance of ocular albinism, what is the chance that a son of a carrier mother will have albinism?

1 in 2 Signup and view all the answers

Which gene is responsible for protecting melanocytes from Reactive Oxygen Species (ROS) damage?

DCT Signup and view all the answers

What are the two main types of albinism?

Oculocutaneous Albinism and Ocular Albinism Signup and view all the answers

Which of the following is NOT a common eye condition associated with albinism?

Astigmatism Signup and view all the answers

Which of the following describes foveal hypoplasia?

Failure of the foveal pit to develop properly Signup and view all the answers

What impact does albinism have on vision?

Poor vision is common even with corrective lenses Signup and view all the answers

Which of the following treatments is recommended for managing skin protection in individuals with albinism?

Sunscreen and protective clothing Signup and view all the answers

What could be an effective accommodation in an academic setting for students with albinism?

Providing enlarged text in presentations Signup and view all the answers

What is the primary characteristic of dystonia?

Involuntary muscle contractions causing twisting movements Signup and view all the answers

Why is genetic counseling important for families with albinism?

It assists in family planning and understanding risks Signup and view all the answers

What is a common misconception about people with albinism?

They should be treated differently than others Signup and view all the answers

Which of the following symptoms is NOT associated with Parkinsonism?

Oculomotor abnormalities Signup and view all the answers

At what age do symptoms of dystonia typically begin?

30s-40s Signup and view all the answers

Which treatment is often used to relieve symptoms of parkinsonism?

Carbidopa/Levodopa Signup and view all the answers

Which of the following disorders may develop alongside parkinsonism?

Dystonia Signup and view all the answers

What genetic mutation is associated with XDP?

TAF1 gene mutation Signup and view all the answers

Which type of dystonia can benefit from botulinum toxin injections?

Focal dystonia Signup and view all the answers

Which additional symptoms might patients with dystonia experience?

Cognitive and psychiatric symptoms Signup and view all the answers

What is the primary focus of oculocutaneous albinism research according to the listed sources?

Inheritance patterns in different populations Signup and view all the answers

Which gene is primarily associated with the development of pigmentation in oculocutaneous albinism?

TYRP1 Signup and view all the answers

Which of the following best describes 'lubag' as mentioned in the context of X-linked dystonia parkinsonism?

A movement disorder endemic to Panay, Philippines Signup and view all the answers

What is the significance of the MC1R gene in relation to albinism?

It is involved in the melanin synthesis process. Signup and view all the answers

What research focus is suggested by studying membrane transport proteins in melanosomes?

Regulation of ion transport for pigmentation Signup and view all the answers

What role does the SLC45A2 gene play in pigmentation disorders?

Influences melanin distribution in skin and hair Signup and view all the answers

Which condition is characterized by both dystonia and parkinsonism, particularly noted in the Panay region?

X-linked dystonia parkinsonism Signup and view all the answers

The research referenced covers various genes involved in albinism. Which gene is NOT directly related to this condition?

GBA Signup and view all the answers

Study Notes

Marfan Syndrome

A genetic disorder inherited from a parental generation, affecting connective tissue.
Primarily affects eyes, heart, blood vessels, and skeleton.
Caused by a defect in the FBN1 gene, creating fibrillin proteins crucial for connective tissues.
Offspring has a 50% chance of inheriting the defective gene from either parent.
First described by Antoine-Bernard Marfan in 1896.
Famous people with Marfan syndrome include Osama Bin Laden, Michael Phelps, and Abraham Lincoln.
Autosomal dominant, with only a parent having the disorder as a risk factor.
25% of cases are sporadic due to novo mutations.
Incidence: 1 in 3000 to 5000 individuals.
Awareness and medical access issues contribute to delayed diagnoses and treatment in the Philippines.

Albinism

A collection of heritable diseases caused by diminished/absent melanin in ectoderm-derived tissues (skin, hair, eyes).
This results in a distinct decrease in skin pigmentation.
Originates from the Latin word "albus," meaning "white".
Two major categories:
- Oculocutaneous Albinism (OCA): Affects skin, hair, and eyes.
- Ocular Albinism (OA): Affects only the visual pathway.
Historical background: Earliest descriptions found in the Book of Enoch, and Pliny's writings.
Sir Archibald Edward Garrrod identified albinism as an inborn error of metabolism.
Common historical misconceptions: sometimes connected to the divine or deemed a negative thing.
Incidence: 1 in 20,000 globally, with variations in regions.
OCA1 is the most common type in Caucasians, followed by OCA2 (more common in Africa).
OCA genetics are passed on in an autosomal recessive pattern. OCA5-8 are rare variants.
OA genetics are passed on in an X-linked pattern, with males showing the trait more frequently, and females generally carriers.

Sex-Linked XDP

XDP is also known as Lubag in American literature.
It manifests as a severe, progressive torsion dystonia initially, lasting for the first 10-15 years.
It might then transform into parkinsonian features later in life.
First noted in the 1970s in Panay, Philippines.
The name reflects the tremor-like movement symptoms.
Inherited through an X-linked recessive pattern.
Primarily affecting males.
Associated with TAFI gene mutations.
Possible links to environmental factors and emotional stress exist.

Treatment/Management

Marfan Syndrome: No cure; focus on relieving symptoms. Doctors might prescribe anti-inflammatory drugs, and angiotensin blockers and beta blockers. Additional therapies might include support for relieving spinal curvature, contacts or glasses, occupational and physical therapy to strengthen muscles, and lifestyle changes.
Albinism: No cure; treatment addresses the resultant issues and involves genetic counseling, vision care (regular eye exams, corrective lenses, low-vision aids), and protective measures for skin (sunscreen, protective clothing, regular check-ups).
XDP: No cure; medications include carbidopa/levodopa (relieves Parkinsonism symptoms), anticholinergics (for muscle issues), and tetrabenazine/zolpidem (for dystonia). Therapies such as Botulinum toxin injections, and Deep Brain Stimulation might help manage symptoms.

Recommendations

Be aware of the characteristics of both diseases
Advocate for better awareness and care for these conditions.
Promote inclusivity and empathy; consider support for affected individuals/communities.
Support research to further understand the diseases; Encourage gathering data and education.

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Description

Explore the genetic disorders Marfan syndrome and albinism in this quiz. Learn about their causes, inheritance patterns, and famous individuals associated with these conditions. This quiz covers the important aspects of these heritable diseases and their impact on affected individuals.