Monogenic hearing loss
Gene: BCS1L
Comment on mode of inheritance: Confirmed on OMIM.Created: 17 Feb 2016, 12:02 p.m.
Inheritance: MitochondrialCreated: 7 Feb 2016, 5:58 a.m.
Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal
Phenotypes
#124000:Mitochondrial complex III deficiency, nuclear type 1[Failure to thrivePoor prenatal growthPoor postnatal growth; Deafness (in some patients); Cataracts (rare); Decreased liver functionBiopsy shows fibrosisCholestasisCholangitisHepatosiderosisMicrovesicular steatosisDecreased complex III activity in liver tissue; Poor feeding; Tubulointerstitial nephritisRenal tubulopathy; Brittle hair (in some patients); HypotoniaMuscle weaknessRagged red fibers seen on muscle biopsyDecreased mitochondrial complex III activityOther mitochondrial complex enzyme activities may also be decreased; Delayed psychomotor developmentMental retardationMitochondrial encephalopathyHyperreflexiaSpasticityMotor dysfunctionSeizuresAbnormal EEGCerebral atrophyCerebellar atrophyWhite matter lesions may occur in the thalami, basal ganglia, and periventricular white matter (see Leigh syndrome,); Lactic acidosisMetabolic acidosisHypoglycemia; Coagulation defect due to decreased liver function; Increased serum lactateAbnormal liver function testsAminoaciduriaDecreased respiratory chain complex III activity in multiple tissues]; #256000:Leigh syndrome[Failure to thrive; OphthalmoplegiaOptic atrophyNystagmusStrabismusPtosisPigmentary retinopathy; Abnormal respiratory patternsRespiratory failure; Hypertrichosis; Hypotonia; Psychomotor retardationHypotoniaAtaxiaDystoniaDysarthriaSpasticityHyperreflexiaSeizuresBrainstem abnormalitiesMental retardationLesions in basal ganglia, brainstem, cerebellum, thalamus, spinal cord characterized by demyelination, necrosis, gliosis, spongiosis, and capillary proliferation; Emotional lability; Lactic acidosis; Increased serum lactateIncreased CSF lactate]; #262000:Bjornstad syndrome[Hearing loss, sensorineural progressive; Light-colored eyes; Hypogonadism (in some patients); Anhidrosis; Pili tortiLoss of hairSparse, short hair growthBrittle hairHair lacks pigment; Mental retardation (in some patients)]
Comment on list classification: Good evidence from OMIM and expertCreated: 1 Feb 2016, 4:51 p.m.
Phenotypes for BCS1L were set to #124000:Mitochondrial complex III deficiency, nuclear type 1; #256000:Leigh syndrome; #262000:Bjornstad syndrome; #603358:GRACILE syndrome
Publications for BCS1L were set to PMID:10508156; 11528392; 12215968; 12910490; 17314340; 17403714; 19162478; 19508421; 24172246; 7577396; 9545407; 9792866; 9878253
Mode of inheritance for BCS1L was changed to BIALLELIC, autosomal or pseudoautosomal
This gene has been classified as Green List (High Evidence).
Mode of inheritance for BCS1L was changed to BIALLELIC, autosomal or pseudoautosomal
This gene has been classified as Green List (High Evidence).
BCS1L was added to Congenital hearing impairment (Profound/Severe)panel. Sources: Expert