Muscular dystrophy and myopathy_Paediatric
Gene: HRAS
A single variant, p.(Glu63Lys), has been identified in two unrelated internal VCGS patients (one confirmed de novo) who had a mixed phenotype of Costello syndrome and congenital myopathy with excess of muscle spindles.
Costello syndrome, congenital myopathy with excess of muscle spindles type (MIM#218040).Created: 12 Jun 2026, 1:13 p.m. | Last Modified: 12 Jun 2026, 1:13 p.m.
Panel Version: 2.0
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
Costello syndrome, congenital myopathy with excess of muscle spindles type (MIM#218040)
A variant of Costello Syndrome which is typically characterised by diffuse hypotonia, short stature, developmental delay etc.
Age of onset - birth to early childhood
Most of the mutations related to CMEMS are inherited in an Autosomal Dominant manner, some can be caused by Somatic mutations as well.
PMID: 17412879
4 unrelated individuals identified with a mutation in HRAS and clinical features causative of congenital myopathy with excess of muscle spindles (CMEMS). No functional evidence or animal model study conducted yet
Sources: OtherCreated: 8 May 2023, 4:19 p.m.
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown
Phenotypes
Congenital myopathy with excess of muscle spindles (MIM#218040)
Publications
Hypotonia is a common feature of Costello syndrome, note reports of abnormal skeletal muscle biopsies in several reported individuals, however, always in conjunction with other phenotypic features of Costello syndromeCreated: 10 Jun 2020, 11:19 a.m.
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
Costello syndrome, MIM# 218040; Congenital myopathy with excess of muscle spindles 218040
Publications
Phenotypes for gene: HRAS were changed from Congenital myopathy with excess of muscle spindles (MIM#218040) to Congenital myopathy with excess of muscle spindles (MIM#218040); Costello syndrome, congenital myopathy with excess of muscle spindles type (MIM#218040)
Gene: hras has been classified as Green List (High Evidence).
Phenotypes for gene: HRAS were changed from Congenital myopathy with excess of muscle spindles (MIM#218040) to Congenital myopathy with excess of muscle spindles (MIM#218040)
Gene: hras has been classified as Amber List (Moderate Evidence).
Gene: hras has been classified as Amber List (Moderate Evidence).
gene: HRAS was added gene: HRAS was added to Muscular dystrophy_Paediatric. Sources: Other Mode of inheritance for gene: HRAS was set to MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown Publications for gene: HRAS were set to 17412879 Phenotypes for gene: HRAS were set to Congenital myopathy with excess of muscle spindles (MIM#218040) Review for gene: HRAS was set to AMBER