Thrombocytopenia in patients with 22q11.2 deletion syndrome and its association with glycoprotein Ib-beta.
OBJECTIVE
To elucidate whether thrombocytopenia in 22q11.2 deletion syndrome patients is associated with the hemizygosity of glycoprotein Ib-beta and to clarify the correlation of phenotype and genotype of this gene in 22q11.2 deletion syndrome patients with thrombocytopenia.


METHODS
Platelet number, mean platelet volume, platelet agglutination, and the protein level of glycoprotein Ib-beta were measured in 22q11.2 deletion syndrome patients and controls. Phenotypes other than that of thrombocytopenia were also analyzed in these patients.


RESULTS
The 22q11.2 deletion syndrome patients with thrombocytopenia had a larger mean platelet volume, lower agglutination to ristocetin, and lower protein level of glycoprotein Ib-beta than control patients. The 22q11.2 deletion syndrome patients with thrombocytopenia showed an increased risk of developing schizophrenia.


CONCLUSIONS
Thrombocytopenia in 22q11.2 deletion syndrome patients is associated with decreased expression of glycoprotein Ib-beta because of the hemizygosity. 22q11.2 deletion syndrome patients with thrombocytopenia require total management, especially for schizophrenia.
Kato
Taichi
T
Department of Pediatrics, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Kosaka
Kazuki
K
Kimura
Misa
M
Imamura
Shin-Ichiro
S
Yamada
Osamu
O
Iwai
Kazumasa
K
Ando
Masahiko
M
Joh-o
Kunitaka
K
Kuroe
Kenji
K
Ohtake
Akira
A
Takao
Atsuyoshi
A
Momma
Kazuo
K
Matsuoka
Rumiko
R
D000293:Adolescent; D000328:Adult; D015153:Blotting, Western; D002648:Child; D002675:Child, Preschool; D002872:Chromosome Deletion; D002892:Chromosomes, Human, Pair 22; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D010641:Phenotype; D010976:Platelet Count; D019038:Platelet Glycoprotein GPIb-IX Complex / Q000235:genetics*; D017422:Sequence Analysis, DNA; D013921:Thrombocytopenia / Q000097:blood / Q000235:genetics*
D019038:Platelet Glycoprotein GPIb-IX Complex