Björnstad syndrome
General Information (adopted from Orphanet):
| Synonyms, Signs: |
PILI TORTI AND NERVE DEAFNESS PTD BJS Deafness - pili torti - hypogonadism |
| Number of Symptoms | 20 |
| OrphanetNr: | 123 |
| OMIM Id: |
262000
|
| ICD-10: |
|
| UMLs: |
C0266006 |
| MeSH: |
C537633 |
| MedDRA: |
|
| Snomed: |
67817003 |
Prevalence, inheritance and age of onset:
| Prevalence: | 33 cases [Orphanet] |
| Inheritance: |
Autosomal recessive [Orphanet] |
| Age of onset: |
Neonatal Infancy [Orphanet] |
Disease classification (adopted from Orphanet):
| Parent Diseases: |
Isolated hair shaft abnormality
-Rare genetic disease -Rare skin disease Mitochondrial disorder due to a defect in assembly or maturation of the respiratory chain complexes -Rare developmental defect during embryogenesis -Rare genetic disease -Rare neurologic disease |
Symptom Information:
|
|
(HPO:0000135) | Hypogonadism | 89 / 7739 | ||||
|
|
(HPO:0200102) | Sparse or absent eyelashes | Very frequent [Orphanet] | 64 / 7739 | |||
|
|
(HPO:0100840) | Aplasia/Hypoplasia of the eyebrow | Very frequent [Orphanet] | 117 / 7739 | |||
|
|
(HPO:0008625) | Severe sensorineural hearing impairment | 150 / 7739 | ||||
|
|
(HPO:0000407) | Sensorineural hearing impairment | Very frequent [Orphanet] | 524 / 7739 | |||
|
|
(HPO:0008527) | Congenital sensorineural hearing impairment | 165 / 7739 | ||||
|
|
(HPO:0001249) | Intellectual disability | rare [HPO:skoehler] | 1089 / 7739 | |||
|
|
(HPO:0003329) | Hair shafts flattened at irregular intervals and twisted through 180 degrees about their axes | 2 / 7739 | ||||
|
|
(HPO:0001596) | Alopecia | Frequent [Orphanet] | 162 / 7739 | |||
|
|
(HPO:0000970) | Anhidrosis | 24 / 7739 | ||||
|
|
(HPO:0011359) | Dry hair | 16 / 7739 | ||||
|
|
(HPO:0003777) | Pili torti | Very frequent [Orphanet] | 24 / 7739 | |||
|
|
(HPO:0002299) | Brittle hair | 15345881 | IBIS | 52 / 7739 | ||
|
|
(HPO:0010720) | Abnormal hair pattern | Very frequent [Orphanet] | 14 / 7739 | |||
|
|
(HPO:0002208) | Coarse hair | 58 / 7739 | ||||
|
|
(HPO:0000007) | Autosomal recessive inheritance | 2538 / 7739 | ||||
|
|
(OMIM) | Dry lusterless hair | 2 / 7739 | ||||
|
|
(OMIM) | Fragile hair | 5 / 7739 | ||||
|
|
(HPO:0003828) | Variable expressivity | 130 / 7739 | ||||
|
|
(MedDRA:10059594) | Secondary hypogonadism | 2 / 7739 |
Associated genes:
ClinVar (via SNiPA)
| Gene symbol | Variation | Clinical significance | Reference |
|---|
Additional Information:
| Description: (OMIM) |
Bjornstad syndrome is an autosomal recessive disorder characterized by sensorineural hearing loss and pili torti. The hearing loss is congenital and of variable severity. Pili torti (twisted hairs), a condition in which the hair shafts are flattened at ... |
| Clinical Description OMIM |
Bjornstad (1965) first commented on this association. Among 8 cases of pili torti, 5 had nerve deafness. Reed (1966) observed 4 additional cases, and Robinson and Johnston (1967) reported a case. Deafness was evident in the first year ... |
| Molecular genetics OMIM |
By DNA sequencing of 44 genes within the critical region for Bjornstad syndrome on chromosome 2q, Hinson et al. (2007) identified mutations in the BCS1L gene (e.g., 603647.0008) in affected members of families segregating for the disorder. ... |