Human Genetic Disorders

These flashcards summarize key concepts regarding human genetic disorders, including types of mutations, associated symptoms, and examples of specific disorders.

What is the result of non-disjunction during meiosis in females as they age?

Increased occurrence of chromosomal mutations, such as Down Syndrome due to errors in chromosome separation.

What are the main characteristics of Down Syndrome (Trisomy 21)?

Short stature, round full face, oversized tongue, and varying degrees of intellectual disabilities.

What is Patau Syndrome and its primary defects?

Patau Syndrome (Trisomy 13) includes neural tube defects, facial clefting, polydactyly, and intellectual disabilities.

What are the symptoms of Klinefelter’s Syndrome (Trisomy XXY)?

Underdeveloped testes, overdeveloped breasts, and infertility, often treated with hormones and surgery.

What is Turner’s Syndrome?

Turner’s Syndrome (Monosomy X, XO) is characterized by unexplained short stature and developmental anomalies such as a webbed neck.

What is Cri-du-chat syndrome?

A deletion at chromosome 5, leading to developmental abnormalities and a distinctive 'cat-like' cry.

What is the genetic cause of Tay-Sachs disease?

A mutation affecting the Hex A protein involved in fat breakdown in brain cells, leads to severe neurological decline.

What causes Albinism?

A mutation in the Tyrosinase protein that prevents melanin production, making individuals sensitive to UV rays.

How does Sickle Cell Anemia affect red blood cells?

Hemoglobin S instead of A causes red blood cells to elongate and sickle, leading to blockages and pain.

What is Phenylketonuria (PKU) and how is it managed?

A genetic disorder caused by a defective enzyme that leads to phenylalanine buildup; managed by strict dietary restrictions.

What is Cystic Fibrosis and its genetic basis?

A disorder caused by mutations in the CFTR gene, leading to thick mucus in lungs and digestive issues; treated with Trikafta.

What is Huntington’s Chorea?

A genetic disorder caused by CAG triplet repeats leading to the degeneration of nerve cells, usually manifesting after age 30.

What is the genetic explanation for Achondroplasia?

Mutation in the FGFR3 gene that causes premature conversion of cartilage to bone, resulting in dwarfism.

What are the characteristics of Marfan Syndrome?

Caused by mutations in the Fibrillin gene; leads to tall stature, long limbs, and joint laxity.

How does Hemophilia affect blood clotting?

A disorder caused by the lack of Factor 8, resulting in the inability to clot blood effectively, treated with clotting factors.

What is Duchenne Muscular Dystrophy?

A condition caused by mutations in the Dystrophin gene, leading to progressive muscle breakdown starting early in childhood.

What is the most common form of colorblindness?

Red-green colorblindness due to defects in receptor proteins responsible for color detection.

What is Fragile X syndrome?

A genetic condition caused by CGG triplet repeats in the FMR1 gene affecting neurological development.