Alterations in the phenotype of neocortical pyramidal cells in the Dyrk1A+/- mouse.

[monosomy 21]

The gene encoding the dual-specificity tyrosine-regulated kinase DYRK 1 A maps to the chromosomal segment HSA 21 q 22 .2 , which lies within the Down syndrome critical region . The reduction in brain size and behavioral defects observed in mice lacking one copy of the murine homologue Dyrk 1 A (Dyrk 1 A +/-) support the idea that this kinase may be involved in monosomy 21 associated mental retardation . However , the structural basis of these behavioral defects remains unclear . In the present work , we have analyzed the microstructure of cortical circuitry in the Dyrk 1 A +/- mouse and control littermates by intracellular injection of Lucifer Yellow in fixed cortical tissue . We found that labeled pyramidal cells were considerably smaller , less branched and less spinous in the cortex of Dyrk 1 A +/- mice than in control littermates . These results suggest that Dyrk 1 A influences the size and complexity of pyramidal cells , and thus their capability to integrate information .

Diseases
Validation

Diseases presenting "mental retardation" symptom

achondroplasia

alexander disease

alpha-thalassemia

aniridia

aromatase deficiency

canavan disease

classical phenylketonuria

coats disease

cohen syndrome

cowden syndrome

cystinuria

dentin dysplasia

familial hypocalciuric hypercalcemia

homocystinuria without methylmalonic aciduria

hydrocephalus with stenosis of the aqueduct of sylvius

kabuki syndrome

kallmann syndrome

lamellar ichthyosis

lymphangioleiomyomatosis

monosomy 21

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