Genetic Syndromes and Disorders

Vocabulary-style flashcards covering the characteristics, genetic causes, and prevalence of Rett, Williams, Cri-du-chat, Cornelia de Lange, Tuberous sclerosis, Angelman, and Prader-Willi syndromes based on lecture notes.

Rett syndrome

A progressive disorder affecting mostly females ($1$ in $10,000$) characterized by normal development for the first $6-18$ months of life followed by symptoms including hand-wringing, microcephaly, and loss of motor function.

MECP2

The gene sporadically mutated on the X chromosome ($Xq28$) to cause Rett syndrome; the mutation typically arises in paternal reproductive cells.

Williams syndrome

A condition caused by a sporadic or autosomal dominant microdeletion of ~$20$ genes on Chromosome $7$, presenting with heart defects in $80\%$ of cases, renal irregularities, and a "star like" iris pattern.

Cri-du-chat syndrome

A disorder also known as $5p-$ ($5p$ minus) caused by a deletion on the short arm of chromosome $5$, characterized by a high-pitched cat-like cry and a $3:1$ female to male ratio.

Hypotonia

A symptom involving decreased muscle tone, identified as a feature of Cri-du-chat syndrome.

Cornelia de lange syndrome

A congenital syndrome often caused by a sporadic mutation of the NIPBL gene on Chromosome $5$, featuring small hands/feet, long eyelashes, bushy eyebrows, and ASD symptomatology.

NIPBL

The gene located on Chromosome $5$ that is sporadically mutated in most cases of Cornelia de lange syndrome.

Tuberous sclerosis

A neurocutaneous genetic syndrome ($1$ in $5,800-30,000$) characterized by benign tumor-like malformations in various tissues, epilepsy, and hypopigmented spots.

TSC1

A gene located on Chromosome $9$ that codes for the protein hamartin and is implicated in Tuberous sclerosis.

TSC2

A gene located on Chromosome $16$ that codes for the protein tuberin and is implicated in Tuberous sclerosis.

Hamartin and Tuberin

Proteins regulated by TSC1 and TSC2 genes that work together to regulate many cellular processes.

Angelman syndrome

A syndrome characterized by ataxic gait, paroxysmal laughter, and minimally verbal status, typically caused by a maternal deletion of genetic material on chromosome $15$.

Paroxysmal laughter

A defining feature of Angelman syndrome involving convulsive or fitful laughter.

UBE3A

The specific single gene on Chromosome $15$ ($15q11-13$) where a mutation can cause Angelman syndrome.

Prader-willi syndrome

A condition caused by a paternal deletion of the $15q11-13$ region of Chromosome $15$, leading to repetitive/compulsive behaviors and a major focus on accessing food.

Hypothalamic functioning

The physiological system impacted in Prader-willi syndrome that regulates satiation and hunger, causing individuals to appear chronically hungry.