DYRK1A mutations in two unrelated patients

Area of Science:

• Genetics
• Neuroscience
• Developmental Biology

Background:

• The DYRK1A gene is implicated in intellectual disability (ID), particularly in Down syndrome.
• Advances in next-generation sequencing (NGS) and array comparative genomic hybridization (aCGH) have facilitated the identification of genetic aberrations in patients with ID.
• DYRK1A mutations are found in over 1% of patients with ID in published NGS studies.

Observation:

• This report describes two unrelated boys with developmental delay, febrile seizures, facial dysmorphism, and brain atrophy.
• Patient 1 exhibited autistic behaviors and micropenis, while Patient 2 had stereotypies and microcephaly.
• NGS identified heterozygous de novo DYRK1A variants: a nonsense mutation (p.Arg205*) in Patient 1 and a missense mutation (p.Ser311Phe) in Patient 2.

Findings:

• Patients with DYRK1A mutations share a common phenotype including developmental delay/ID, autism spectrum disorder behaviors, microcephaly, epileptic seizures, and specific facial dysmorphisms.
• Observed facial features include ear anomalies, thin lips, short philtrum, and frontal bossing.
• The frequency of these clinical features in DYRK1A mutation patients is detailed.

Implications:

• The findings contribute to a better definition of the DYRK1A encephalopathy phenotype.
• Recognizing this phenotype can aid in the diagnosis of neurodevelopmental disorders.
• Establishing genotype-phenotype correlations for DYRK1A mutations remains a future challenge.