Genetic Disease Case Study: Adrenoleukodystrophy (ALD)

What is Adrenoleukodystrophy (ALD)?

In this case study, you will investigate characteristics and type of inheritance of a genetic disease in addition to how it affects cells, tissues and organs of the human body. You will make connections between genetic diseases and their effects on organelles, cells and tissues as discussed in this course. Research about your assigned genetic disease to answer the questions below. Choose the most correct answer.

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Your assigned disease: Adrenoleukodystrophy (ALD) The following websites are good places to start to begin your research:

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http://wvvw.mayoclinic oro/diseases-conditions

https://ww-w.genome.gov/1 0001204/s ecific- enetic-disorders/�

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Multiple Choice Question: Choose the most correct answer for each of the following questions about your assigned disease.

1. What pattern of genetic inheritance does your disease follow?

a) Autosomal Dominant� �

b) Autosomal Recessive�
c) Sex-linked recessive�

2. Which category of tissues is most directly affected by your disorder?

a) Connective Tissue

b) Muscular Tissue

c) Nervous Tissue

d) Epithelial Tissue�

3. Which chromosome is affected?

a) Chromosome 9

b) Chromosome 13

c) Chromosome 15

d) Chromosome X�

4. Which gene is primarily affected in people with ALD?

a) peroxisomc gene

b) VLCFA gene

c) ABCD I gene�
d) Chromosome Y�
e) ALD 1 & 2 genes�

5. The normal functioning of the gene in Question 4 allows for:

a) the normal flow of water and salt in tissues

b) very long chain fatty acids are transported and processed within the cells so they don't accumulate in the body

c) muscles to contract and move in a controlled and smooth manner

d) normal digestion of protein

e) long chain polysaccharides to be digested within cell of the digestive system

6. What are the early physical effects of the abnormal �protein on the body?

a) Aggression, poor memory and problems with speech, vision, swallowing and walking are noticed.

b) High levels of sugar build up causing mucus production in the lungs and digestive system.

c) Skeletal muscle begins to waste away causing paralysis.

d) Vision problem occur so the patient has difficulty seeing different colours.

e) The smooth muscle that lines blood vessels loses it strength, causing expansion and eventual rupture of blood vessels.�

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7. What is the effect of the mutated gene on the �ALD protein? �

a) ALD protein is produced is very high amounts.

b) ALD protein is produced in very low amounts or even none at all.

c) ALD protein is produced in normal amounts but it is not working.

Type of inheritance followed by ALD

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8. Which organelle is mainly affected in ALD?

a) Centrioles

b) Peroxisomes

c) Golgi Body�
d) Mitochondria�
e) Cilia�

9. At which stage in human development do you typically begin to seehetp____AolyM of this disease?

a) In childhood

b) In late adulthood

c) In the elderly�

10. Which part of the body is NOT usually affected by your disorder?

a) adrenal glands

b) myelin

c) skeletal muscles

d) lungs�

e) neurons

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11. Can you easily identify your disease using a karyotype?

A) YES

B) NO�

12. Which of the following is the correct genotype of a person with ALD? Let the letter Ala represent ALD.

a) AA

b) aa

c) XAY

d)XaXa

e) xay

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13. A son was born with ALD, though his father does not have ALD. What are their respective genotypes�(son, father)?

a) aa, AA

b) Aa, AA

c) XaY, XAY

d) XaYA, XAY

e) XAY, XaY

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14. What are the chances of a boy being born with ALD if his mother is homozygous dominant for ALD?

a) 0%

b) 25%

c) 50%

d) 75%

e) 100

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15. Jill does not have ALD, but her brother does. Jack does not have ALD. Is there any chance that a boy could be born with ALD if Jack and Jill have children?

a) Yes

b) No

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16. A mother carries one dominant and one recessive allele for ALD. The father carries a dominant allele. If they have a daughter, what is the probability that she will be a carrier for ALD?

a) 0%�

b) 25%

c) 50%

d) 75%

e) 100%�

17. A mother carries one dominant and one recessive allele for ALD. The father carries a dominant allele. If a daughter, what is the probability that she will NOT have ALD?�

a) 0%�

b) 25%

c) 50%

d) 75%

e) 100%�

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18. A mother carries one dominant and one recessive allele for ALD. The father carries a dominant allele. If they have a son, what is the probability that he will inherit ALD?

a) 0%

b) 25%

c) 50%

d) 75%

e) 100%�

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19. A mother carries two recessive alleles for ALD. The father carries a dominant allele. If they have a son, what is the probability that he will be born with ALD?

a) 0%

b) 25%

c) 50%

d) 75%

e) 100%�

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True or False: Select 'A' for TRUE '13' for FALSE on our card for 1 questions 20-23. 20. Females can be carriers of ALD but males can not.

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21. Fathers can not pass their allele for ALD to their daughters.

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22. ALD is more common among males than females.

23. Which of the images below could illustrate the pattern of inheritance of ALD?�

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Use the illustration below which represents your disease to -mover the next 7 question.

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24. What is the scientific name given to the above illustration?

a) Karyotype

b) Punnett Square

c) Pedigree

25. 1-Tow many generations are illustrated in the above diagram?

a) 1

b) 2

c) 3�
d) Hybrid Cross�
d) 4�
e) 15�

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26. Which of the following is the most correct genotype of Individual 2?

a) AA

b) Aa

c) aa

d) XAY

e) XaY

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27. Which of the following is the most correct phenotype of Individual 1?

a) Male with ALD

b) Female with ALD

c) Male, no ALD

d) Female, no ALD

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28. Which of the following is the most correct genotype for Individual 8?

a) XAXA

b) XaXa

c) aa d) XAXa

e) A or D

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29. Which of the following is the most correct genotype for Individual 13?

a) XaXa

b) Aa

c) X"Y

d) aa e) XaY

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30. Which of the following is the most correct �genotype for Individual 12?

a) XAXA

b) aa

c) XaXa

d) XAXa

e) A or D