Last Updated: October 31, 2022 Introduction to Beckwith-Wiedemann Syndrome Beckwith-Wiedemann syndrome (BWS) is the most well characterized disorder affecting growth that results from defects in the process of genomic imprinting. The overall frequency of BWS is 1 in...
Diseases Associated with DNA Abnormalities
Prader-Willi Syndrome
Diseases and Disorders, Diseases Associated with DNA Abnormalities, DNA Imprinting Disorders
Last Updated February 27, 2023 Introduction to Prader-Willi Syndrome Prader-Willi syndrome (PWS) was first described in 1887 by John Langdon Down who also identified Down syndrome. The full spectrum of PWS was reported in 1956 by Andrea Prader, Alexis Labhart, and...
Angelman Syndrome
Diseases and Disorders, Diseases Associated with DNA Abnormalities, DNA Imprinting Disorders
Last Updated: August 3, 2023 Introduction to Angelman Syndrome Angelman syndrome (AS) is named after the English physician Harry Angelman who first described the disorder in 1965. He observed three children with a similar constellation of symptoms and he referred to...
Myotonic Dystrophy, DM1
Diseases and Disorders, Diseases Associated with DNA Abnormalities, Trinucleotide Repeat Disorders
Last Updated: September 25, 2024 Introduction to Myotonic Dystrophy Type 1 myotonic dystrophy (originally abbreviated DM1 for the Latin dystrophia myotonica) is the most commonly occurring form of muscular dystrophy in adults. The disease manifests in nearly 1 in...
Fragile XE Syndrome
Diseases and Disorders, Diseases Associated with DNA Abnormalities, Trinucleotide Repeat Disorders
Last Updated: September 15, 2022 Introduction to Fragile XE Syndrome Fragile XE syndrome (previously referred to as fragile XE mental retardation) is an X-linked dominant disorder that is defined by patients who have the cytogenetic changes associated...
Fragile X Syndrome
Diseases and Disorders, Diseases Associated with DNA Abnormalities, Trinucleotide Repeat Disorders
Last Updated: November 6, 2022 Introduction to Fragile X Syndrome Fragile X syndrome is an X-linked dominant disorder representing the most common form of inherited intellectual impairment. Fragile X syndrome occurs with a frequency of approximately 1 in 4000 males...
Dentatorubral-Pallidoluysian Atrophy, DRPLA
Diseases and Disorders, Diseases Associated with DNA Abnormalities, Trinucleotide Repeat Disorders
Last Updated: September 15, 2022 Introduction to Dentatorubral-Pallidoluysian Atrophy Dentatorubral-pallidoluysian atrophy (DRPLA) is a progressive neurodegenerative disease resulting from the expansion of a CAG trinucleotide repeat in the atrophin-1 gene. Normal...
Spinocerebellar Ataxias, SCA
Diseases and Disorders, Diseases Associated with DNA Abnormalities, Trinucleotide Repeat Disorders
Last Updated: May 15, 2024 Introduction to the Spinocerebellar Ataxias The spinocerebellar ataxias (SCA) represent a group of autosomal dominant neurological disorders characterized by variable degrees of degeneration in the cerebellum, spinocerebellar tracts, and...
Spinobulbar Muscular Atrophy, SBMA
Diseases and Disorders, Diseases Associated with DNA Abnormalities, Trinucleotide Repeat Disorders
Last Updated: March 3, 2023 Introduction to Spinobulbar Muscular Atrophy Spinobulbar muscular atrophy (SBMA) is an adult onset, slowly progressive motor neuropathy that results from the expansion of a CAG trinucleotide repeat in exon 1 of the androgen receptor (AR)...
Huntington Disease, HD
Diseases and Disorders, Diseases Associated with DNA Abnormalities, Trinucleotide Repeat Disorders
Last Updated: March 3, 2023 Introduction to Huntington Disease Huntington disease is inherited as an autosomal dominant disorder characterized by slowly progressive neurodegeneration associated with choreic movements (abnormal involuntary movements) and dementia. The...