del(2)(q31.1)
Synopsis
microcephaly
narrow forehead (short bifrontal diameter)
paresis of ocular muscles/squint
high vaulted and narrow palate
irregularities of length/shape of fingers
syndactyly of fingers
clinodactyly of 5th finger
irregular length or shape of toes
hallux valgus
mental retardation
developmental retardation
skeletal abnormalities of the hands and feet
- upper limbs - mild syndactyly of 2/3 and 3/4 fingers
- short middle phalanges
- clinodactyly of the fifth finger at the distal interphalangel joint on both hands
- bilateral symphalangism of the metacarpal-phalangeal joints of the second and fifth fingers
- symphalangism of metatarsal-phalangeal joint of second, third, and fourth toes on both feet
- fusion of the middle and distal phalanges of the second and fifth toes and hallux valgus bilaterally
- symphalangism
- increased body hair (hypertrichosis)
- abnormal great toe
- long (prehensile) great toe
- short great toe
- broad/bifid great toe
- dorsiflexed great toe
- metatarsus adductus
- hallux valgus
*wide space between first and second toes
- other great toe defect
Physiopathology
Microdeletion 2q31 did not include the HOXD cluster.
Malformations may be caused by deletion of a regulatory element far upstream of the HOXD cluster.
References
Svensson, A. M. et al. ’Detection of a de novo interstitial 2q microdeletion by CGH microarray analysis in a patient with limb malformations, microcephaly and mental retardation’, Am J Med Genet, 143A: 1348-1353, 2007