Are 22q11.2 distal deletions associated with math difficulties?

[22q11.2 deletion syndrome]

Approximately 6 % of school -aged children have math difficulties (MD ). A neurogenetic etiology has been suggested due to the presence of MD in some genetic syndromes such as 22 q 11 .2 DS . However , the contribution of 22 q 11 .2 DS to the MD phenotype has not yet been investigated . This is the first population-based study measuring the frequency of 22 q 11 .2 DS among school children with MD . Children (1 ,564 ) were identified in the schools through a screening test for language and math . Of these children , 152 (82 with MD and 70 controls ) were selected for intelligence , general neuropsychological , and math cognitive assessments and for 22 q 11 .2 microdeletion screening using MLPA . One child in the MD group had a 22 q 11 .2 deletion spanning the LCR 22 -4 to LCR 22 -5 interval . This child was an 11 -year -old girl with subtle anomalies , normal intelligence , MD attributable to number sense deficit , and difficulties in social interactions . Only 19 patients have been reported with this deletion . Upon reviewing these reports , we were able to characterize a new syndrome , 22 q 11 .2 DS (LCR 22 -4 to LCR 22 -5 ), characterized by prematurity ; pre- and postnatal growth restriction ; apparent hypotelorism , short /upslanting palpebral fissures ; hypoplastic nasal alae ; pointed chin and nose ; posteriorly rotated ears ; congenital heart defects ; skeletal abnormalities ; developmental delay , particularly compromising the speech ; learning disability (including MD , in one child ); intellectual disability ; and behavioral problems . These results suggest that 22 q 11 .2 DS (LCR 22 -4 to LCR 22 -5 ) may be one of the genetic causes of MD .

Diseases
Validation

Diseases presenting "developmental delay" symptom

22q11.2 deletion syndrome

achondroplasia

alexander disease

alpha-thalassemia

aniridia

canavan disease

child syndrome

classical phenylketonuria

coats disease

cohen syndrome

congenital diaphragmatic hernia

congenital toxoplasmosis

cowden syndrome

gm1 gangliosidosis

harlequin ichthyosis

hirschsprung disease

holt-oram syndrome

homocystinuria without methylmalonic aciduria

kabuki syndrome

kallmann syndrome

krabbe disease

lamellar ichthyosis

monosomy 21

neonatal adrenoleukodystrophy

phenylketonuria

primary hyperoxaluria type 1

proteus syndrome

pyruvate dehydrogenase deficiency

sneddon syndrome

triple a syndrome

wolf-hirschhorn syndrome

zellweger syndrome

This symptom has already been validated