Cardiomyopathy_Paediatric

Gene: NDUFB11

Green List (high evidence)

Variable syndromic features have been observed in affected individuals, however anaemia and cardiomyopathy appear to be consistent features in males and females, respectively (PMID: 28050600, PMID: 30423443, PMID: 27488349).

It has been suggested that heterozygous females do not display the severe phenotype associated with mitochondrial complex 1 deficiency due to highly skewed XCI favouring expression of the wild type allele, whereas these null variants result in a severe lethal disorder in hemizygous males (PMID: 25772934). Affected females have previously been reported with inherited pathogenic variants from their unaffected mothers. It has been suggested that this may be due to patterns of somatic X-chromosome inactivation, mosaicism or additional genetic or external factors (PMID: 28050600).

Affected females have been reported with null alleles, whereas affected males have only been identified with missense variants or a recurrent single residue in-frame deletion, suggesting that some residual enzyme activity is required for males to be viable, whereas complete loss of function variants may be lethal when hemizygous (PMID: 30423443). Note: female carriers of missense variants have not been reported as clinically affected. Western blots from cells of male patients with the recurrent F93del variant showed reduced protein levels, and recombinant cells demonstrated a proliferation defect, consistent with the anaemia phenotype (PMID: 27488349).

Created: 24 Jun 2021, 1:43 a.m. | Last Modified: 24 Jun 2021, 1:43 a.m.

Panel Version: 0.92

Mode of inheritance
X-LINKED: hemizygous mutation in males, monoallelic mutations in females may cause disease (may be less severe, later onset than males)

Phenotypes
Linear skin defects with multiple congenital anomalies 3, XLD (MIM#300952); Mitochondrial complex I deficiency, nuclear type 30, XLR (MIM#301021)

Publications

• 28050600
• 27488349
• 30423443
• 27488349