Connexion

GENATLAS PHENOTYPE

last update : 11-01-2012

Symbol	DEL22Q11D
Location	22q11.21
Name	chromosome 22q11.2 microdeletion syndrome, distal to the DG/VCF typically deleted region
Other name(s)	monosomy 22q11.2 distal to DGSCR
Corresponding gene	BCR , MAPK1
Other symbol(s)	del22q11.2, dup22q11.2
Main clinical features	prematurity, prenatal and postnatal growth restriction, learning difficulties and/or developmental delay, characteristic facial features, skeletal abnormalities, and increased incidence of a specific type of heart defect, truncus arteriosus common facial dysmorphic features: arched eyebrows, flattened midface, smooth philtrum, thin upper lip, hypoplastic alae nasi, and a small, pointed chin. diaphragmatic hernia and uterine didelphys associated with the distal microdeletion syndrome; and frontomedial polymicrogyria and callosal agenesis associated with the distal microduplication syndrome, 3 patients with Goldenhar syndrome PMID: 21671380
Genetic determination	chromosomal
	genomic disorder
Function/system disorder	mental retardation
	multisystem/generalized
Type	MCA/MR

Gene product

Name

spanning approximately 20 genes, among which MAPK1 could be a candidate gene for low birth weight and prematurity

Mechanism(s)

Gene mutation	Chromosome rearrangement	Effect	Comments

	deletion	haploinsufficiency	either a ~1.4 Mb or ~2.1 Mb recurrent deletion flanked proximally by LCR22-4 and distally by either LCR22-5 or LCR22-6, respectively.

Remark(s)

some cases have been fortuitously detected using the LSI BCR control FISH probe

craniofacial and cardiac outflow tract defects observed in patients with a distal 22q11.2 micro-deletion are explained by deficiencies in neural crest autonomous MAPK1 signaling

Genotype/Phenotype correlations

no clear difference in the severity or the phenotype between the larger ~2.1 Mb deletion and the smaller nested ~1.4 Mb deletion; reciprocal 2.1 Mb duplication was reported; 1 case encompassing SMARCB1 with Goldenhar syndrome and brain tumor(AT/RT); a novel recurrent 22q11 deletion that spans LCR22-4 and partially affects the common 22q11.2 deletion syndrome and the distal 22q11 deletion syndrome in a normally developing girl with growth delay, microcephaly, and truncus arteriosus denote the genes CRKL and MAPK1 as the highest ranking candidates for causing congenital heart disease PMID: 22318985;;