Genetic_Diseases_Flashcards
Approximately how many genetic diseases are there worldwide?
About 6,000 genetic diseases.
What is the difference between congenital and acquired diseases?
Congenital diseases are present at birth; acquired diseases develop later due to external factors.
What causes genetic diseases?
Dysfunction of one or more genes.
What are monogenic or monofactorial diseases?
Diseases caused by a single gene dysfunction.
Are all genetic diseases inherited?
No, some result from somatic mutations and are not passed down.
Give an example of a genetic disease that is not inherited.
Most cancers resulting from mutations in somatic cells.
What are the three main types of genetic diseases discussed?
Mendelian, mitochondrial, and multifactorial diseases.
What characterizes Mendelian diseases?
They follow Mendel’s laws and are caused by single gene mutations.
Name the four modes of inheritance in Mendelian diseases.
Autosomal dominant, autosomal recessive, X-linked dominant, X-linked recessive.
How are mitochondrial diseases inherited?
Exclusively from the mother via mitochondrial DNA.
What causes mitochondrial diseases?
Dysfunction in the mitochondrial genome leading to energy production failure.
List some common symptoms of mitochondrial diseases.
Gastrointestinal issues, diabetes, neurological problems, movement disorders.
How common are mitochondrial diseases?
They affect approximately 1 in 5,000 individuals.
What characterizes multifactorial diseases?
They result from multiple genes and environmental factors.
Do multifactorial diseases follow clear Mendelian inheritance patterns?
No, they do not have clear risk probabilities like Mendelian diseases.
Give examples of multifactorial diseases.
Schizophrenia, diabetes, asthma, hypertension, Alzheimer’s disease, dandruff.
What is the purpose of genetic family trees?
To visualize family history and understand phenotypic transmission patterns.
In autosomal dominant inheritance, how many mutated alleles cause disease?
One mutated allele is sufficient.
What is the chance an affected individual will transmit an autosomal dominant disease to a child?
50% chance for each child.
Give an example of an autosomal dominant disease.
MODY (Maturity Onset Diabetes of the Young).
In autosomal recessive inheritance, how many mutated alleles are needed for disease manifestation?
Two mutated alleles (one from each parent).
Name examples of autosomal recessive diseases.
Sickle cell disease, cystic fibrosis, Tay-Sachs disease.
Where is the mutated gene located in X-linked diseases?
On the X chromosome.
In X-linked dominant inheritance, is one mutated allele enough to cause disease?
Yes, one mutated allele on the X chromosome is sufficient.
Provide examples of X-linked dominant diseases.
Vitamin D resistant rickets, Rett syndrome.
In X-linked recessive inheritance, why are males more affected?
Males have one X chromosome; a single mutated allele causes disease.
Can fathers pass X-linked recessive diseases to their sons?
No, fathers cannot transmit X-linked genes to sons.
Name examples of X-linked recessive diseases.
Red-green color blindness, hemophilia A and B.
What is heterozygote advantage?
When carriers of one mutated allele have a survival benefit.
How does sickle cell trait provide a heterozygote advantage?
Carriers are more resistant to malaria than non-carriers.
What is OMIM?
Online Mendelian Inheritance in Man®, a database of human genes and genetic phenotypes.
What focus does OMIM have?
The relationship between genotype and phenotype.
Why are genetic family trees important in genetics?
They help trace inheritance patterns and predict disease risks.
What is the inheritance pattern when a mother carries an X-linked dominant mutation?
Both sons and daughters have a 50% chance of being affected.
What is the inheritance pattern when a father carries an X-linked dominant mutation?
All daughters are affected; sons are not affected.
