Table 3.
Clinical features of linkeropathies.
| Genes | B3GAT3 | B4GALT7 | B3GALT6 | SLC39A13 | XYLT1 | XYLT2 |
|---|---|---|---|---|---|---|
| Number of patients | n = 26 | n = 32 | n = 46 | n = 9 | n = 28 | n = 20 |
| Skeletal | ||||||
| Short stature | 18/23 | 29/29 | 36/46 | + | + | 7/17 |
| Joint hypermobility | 10/19 | + | 37/46 | + | 13/14 | 2/5 |
| Joint dislocation | 9/25 | + | 37/46 | + | 14/14 | na |
| Joint contractures (hands, elbow) | 19/24 | 4/9 | 30/46 | 3/9 | 4/5 | na |
| Low bone density/osteopenia | 10/11 | 6/32 | 20/46 | 7/9 | 2/2 | 15/15 |
| Multiple fractures | 8/18 | 1/10 | 21/46 | na | na | 19/19 |
| Kypho/scoliosis | 8/24 | 7/32 | 32/46 | 1/7 | 10/12 | 12/13 |
| Platyspondyly | 1/20 | - | 13/36 | + | 5/9 | 18/18 |
| Peculiar fingers a | 25/25 | 1/30 | 13/36 | 7/7 | 19/20 | 9/12 |
| Foot deformity b | 22/25 | 9/10 | 24/46 | 8/8 | 9/13 | 12/12 |
| Pectus excavatum/carinatum | 3/19 | 1/1 | 2/10 | na | 10/12 | 4/4 |
| Radioulnar synostosis | 11/13 | 18/31 | 1/36 | - | na | na |
| Metaphyseal flaring | 3/5 | 4/8 | 23/46 | 4/6 | 4/4 | 0/1 |
| Monkey-wrench femora | 0/4 | 1/2 | na | na | 11/12 | na |
| Iliac abnormalities | 2/4 | - | 27/46 | - | 4/4 | 2/2 |
| Radial head subluxation or dislocation | 3/5 | 17/31 | 15/36 | 3/6 | 1/1 | na |
| Bowing of limbs | 5/19 | 7/32 | 13/46 | 8/8 | 5/5 | na |
| Advance bone age/carpal ossification | 0/10 | 1/32 | 5/16 | na | 13/14 | - |
| Craniofacial | ||||||
| Midface hypoplasia | 24/25 | na | 8/10 | 0/6 | 1/1 | na |
| Flat face | 1/4 | 29/32 | 22/36 | 1/1 | 18/18 | na |
| Craniosynostosis | 12/15 | 6/8 | 1/36 | - | na | na |
| Frontal bossing | 4/12 | - | 29/46 | + | na | na |
| Wide forehead | 2/5 | 29/32 | na | na | 1/1 | 1/1 |
| Blue sclerae | 8/17 | 6/10 | 30/46 | + | 5/6 | 2/6 |
| Proptosis or prominent eyes | 12/14 | 28/30 | 20/46 | + | 6/7 | na |
| Wide-spaced eyes | 3/7 | 28/32 | - | 1/1 | 1/1 | 4/4 |
| Low-set ears | 2/8 | 7/10 | 20/46 | na | na | 4/4 |
| Depressed nasal bridge | 13/20 | - | 10/46 | 1/1 | 21/21 | 4/4 |
| Small mouth/microstomia | 10/19 | 28/30 | - | - | 2/2 | na |
| Long upper lip/long philtrum | 4/4 | - | 15/36 | na | 6/6 | 1/1 |
| Cleft palate/bifid uvula | 4/4 | 4/31 | 6/46 | 3/8 | 7/16 | na |
| Micrognathia | 9/17 | 3/32 | 14/46 | - | 3/3 | na |
| Short and/or webbed neck | 13/19 | - | - | 8/8 | 5/5 | 4/4 |
| Abnormal dentition | 1/2 | 6/10 | 17/46 | 8/9 | 3/5 | 2/14 |
| Ocular | ||||||
| Refractive errors/hypermetropia | 3/5 | 12/29 | 1/10 | 1/9 | 1/5 | 14/14 |
| Clouded cornea | 2/4 | 1/30 | 1/46 | - | 0/5 | na |
| Cataract | 0/26 | 0/30 | na | na | 0/5 | 18/20 |
| Retinal detachment | 0/26 | Na | na | na | 0/5 | 9/16 |
| Cutaneous | ||||||
| Hyperextensible, soft, doughy, thin, translucent skin; cutis laxa | 4/15 | 30/32 | 29/46 | + | 2/2 | 1/5 |
| Atrophic scarring | 1/5 | 4/32 | 10/46 | 5/7 | na | na |
| Other | ||||||
| Cardiovascular abnormalities | 13/20 | - | 2/36 | - | 1/9 | 7/19 |
| Muscle hypotonia | 6/7 | 10/32 | 21/46 | 3/3 | 2/2 | 10/10 |
| Delayed motor development | 5/5 | 8/10 | 12/46 | 3/6 | 10/13 | 6/13 |
| Delayed cognitive development | 1/18 | 19/32 | 14/46 | 0/6 | 17/19 | 9/17 |
| Deafness | 1/3 | 2/32 | 2/46 | - | 2/8 | 12/20 |
Note: na, not available; +, present in all patients; -, absent in all patients; a: Peculiar fingers including long, slender, tapered, broad, thin, arachnodactyly; b: Foot deformity including pes planus, hallux valgus, club feet, sandal gap; B3GAT3: ([26,47,48,49,50,51,52,53], present patient); B4GALT7: [15,16,17,18,19,20,21,32]; B3GALT6: [22,23,24,25,26,27,28], SLC39A13: [29,30,31], XYLT1: [33,34,35,36,37,38,39,40]; XYLT2: [41,42,43,44,45,46].