Bone Marrow Failure

Gene: RAP1B

I don't know

PMID: 32627184 describes 2 patients.
36 yo patient of non-consanguineous parents. Had unclear pancytopenia, multiple congenital malformations, mild intellectual disability, endocrine disorders (short stature with growth hormone deficiency), dysmorphism and other features. Parents and sibling unaffected.
13 yo of non-consanguineous parents with thrombocytopenia, multiple congenital anomalies and learning difficulties. He had normal developmental milestones, walk was achieved at 14 months and there was no speech delay. He attended mainstream school with auxiliary help because of learning difficulties with graphism, syntaxic comprehension, logical reasoning and attention deficit. Parents and siblings unaffected.

PMID: 26280580 describes another patient with variant in RAP1B. The clinical features can be found in supplementary table 2. The table lists ID, but doesn't say severity and lists a host of other features including short stature, facial dysmorphism and skeletal findings. Cytopenia is not a feature for this patient.

PMID 35451551: New patient reported with mild intellectual disability, bicuspid aortic valve, dilation of aortic root and ascending aorta, hearing loss, and long‐standing thrombocytopenia with lymphopenia. Found to have a novel, missense mutation in RAP1B (p.Ala59Gly) - neighbouring amino acid to one of the previously reported variants.
Sources: Expert list

Created: 2 Sep 2023, 3 a.m.

Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted

Phenotypes
Thrombocytopenia 1 with multiple congenital anomalies and dysmorphic facies, MIM# 620654

Publications

• 35451551
• 32627184
• 26280580