Connexion

GENATLAS PHENOTYPE

last update : 25-08-2010

Symbol	DEL2Q31
Location	2q31.1
Name	chromosome 2q interstitial deletion, including 2q31.1
Other name(s)	2q31 monosomy
Corresponding gene	HOXD@ , CHN1 , DLX1 , DLX2 , SP3 , EVX2
Other symbol(s)	MDLGS, DUP2Q31
Main clinical features	limb abnormalities ranging from mild digital abnormalities including syndactyly and brachysyndactyly to more severe malformations such as split hand, split foot or monodactyly abnormalities of other organ systems such as ocular, genital or cardiac defects microcephaly, developmental delay, mild facial dysmorphology, scoliosis, growth retardation have also been reported
Genetic determination	chromosomal
Function/system disorder	osteo-articular
Type	malformation

Gene product

Name

deletion of one or several regulatory elements located far upstream of the HOXD cluster is likely implicated

Mechanism(s)

Gene mutation	Chromosome rearrangement	Effect	Comments

	deletion		not always including HOXD cluster
	deletion		a 3.4 Mb deletion including the entire HOXD gene cluster in a three-generation family presenting duplication of great toes with clinodactyly

Remark(s)

duplication of the HOXD cluster locus associated with mesomelic dysplasia, Kantaputra type (see MMDK)PMID: 20648051 , or syndactyly and nystagmus, PMID: 21654727

Genotype/Phenotype correlations

hemizygosity for one or more genes mapping proximal to the HOXD cluster may contribute to the extremely severe limb defects seen in two unrelated patients with overlapping deletions del(2)(q24.2q31) and del(2)(q31.1q31.2) ; a deletion of 2Mb at 2q31.1 not including the HOXD cluster was present in a patient with symphalangism, microcephaly and mental retardation