Rasopathy
Gene: MAPK1
Motta et al (2020 - PMID: 32721402) report on 7 unrelated individuals harboring de novo missense MAPK1 pathogenic variants.
The phenotype corresponded to a neurodevelopmental disorder and - as the authors comment - consistently included DD, ID , behavioral problems. Postnatal growth delay was observed in approximately half. Hypertelorism, ptosis, downslant of palpebral fissures, wide nasal bridge as low-set/posteriorly rotated ears were among the facial features observed (each in 3 or more subjects within this cohort). Together with short/webbed neck and abnormalities of skin (lentigines / CAL spots) and growth delay these led to clinical suspicion of Noonan s. or disorder of the same pathway in some. Congenital heart defects (ASD, mitral valve insufficiency, though not cardiomyopathy) occurred in 4/7. Bleeding diathesis and lymphedema were reported only once.
MAPK1 encodes the mitogen-activated protein kinase 1 (also known as ERK2) a serine/threonine kinase of the RAS-RAF-MEK-(MAPK/)ERK pathway.
MAPK1 de novo variants were identified in all individuals following trio exome sequencing (and extensive previous genetic investigations which were non-diagnostic).
The distribution of variants, as well as in silico/vitro/vivo studies suggest a GoF effect (boosted signal through the MAPK cascade. MAPK signaling also upregulated in Noonan syndrome).
Sources: LiteratureCreated: 1 Aug 2020, 1:28 a.m.
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
Noonan syndrome 13, MIM#619087; Global developmental delay; Intellectual disability; Behavioral abnormality; Growth delay; Abnormality of the face; Abnormality of the neck; Abnormality of the cardiovascular system; Abnormality of the skin
Publications
Phenotypes for gene: MAPK1 were changed from Global developmental delay; Intellectual disability; Behavioral abnormality; Growth delay; Abnormality of the face; Abnormality of the neck; Abnormality of the cardiovascular system; Abnormality of the skin to Noonan syndrome 13, MIM#619087; Global developmental delay; Intellectual disability; Behavioral abnormality; Growth delay; Abnormality of the face; Abnormality of the neck; Abnormality of the cardiovascular system; Abnormality of the skin
Gene: mapk1 has been classified as Green List (High Evidence).
Gene: mapk1 has been classified as Green List (High Evidence).
gene: MAPK1 was added gene: MAPK1 was added to Rasopathy. Sources: Literature Mode of inheritance for gene: MAPK1 was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted Publications for gene: MAPK1 were set to 32721402 Phenotypes for gene: MAPK1 were set to Global developmental delay; Intellectual disability; Behavioral abnormality; Growth delay; Abnormality of the face; Abnormality of the neck; Abnormality of the cardiovascular system; Abnormality of the skin Review for gene: MAPK1 was set to GREEN