A novel microdeletion in 1(p34.2p34.3), involving the SLC2A1 (GLUT1) gene, and severe delayed development.
A de novo 4.1-megabase microdeletion of chromosome 1p34.2p34.3 has been identified by array-based comparative genomic hybridization in a young male with severely delayed development, microcephaly, pronounced hypotonia, and facial dysmorphism. The deleted region encompasses 48 genes, among them the glucose transporter 1 (SLC2A1 or GLUT1) gene. The deletion of the GLUT1 gene was in line with the abnormal ratio of cerebrospinal fluid (CSF) glucose to blood glucose, indicative of GLUT1 deficiency syndrome (MIM #606777). GLUT1 deficiency syndrome is characterized by therapy-resistant infantile seizures, developmental delay, acquired microcephaly, spasticity, ataxia, and a low concentration of glucose in the CSF. It is known that a ketogenic diet can lead to better control of seizures. This case study shows that identifying a microdeletion as the cause of learning disability is not only important for genetic counselling but might also lead to therapeutic intervention.
Vermeer
Sascha
S
Department of Human Genetics, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
Koolen
David A
DA
Visser
Gepke
G
Brackel
Hein J L
HJ
van der Burgt
Ineke
I
de Leeuw
Nicole
N
Willemsen
Michèl A A P
MA
Sistermans
Erik A
EA
Pfundt
Rolph
R
de Vries
Bert B A
BB
D000015:Abnormalities, Multiple / Q000235:genetics; D001786:Blood Glucose / Q000378:metabolism; D001921:Brain / Q000473:pathology; D002872:Chromosome Deletion; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics*; D019465:Craniofacial Abnormalities / Q000235:genetics; D002658:Developmental Disabilities / Q000235:genetics*; D051272:Glucose Transporter Type 1 / Q000235:genetics*; D006801:Humans; D007223:Infant; D008607:Intellectual Disability / Q000235:genetics; D008279:Magnetic Resonance Imaging; D008297:Male; D008831:Microcephaly / Q000175:diagnosis / Q000235:genetics; D009693:Nucleic Acid Hybridization; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D011596:Psychomotor Disorders / Q000235:genetics
D001786:Blood Glucose; D051272:Glucose Transporter Type 1; C495677:SLC2A1 protein, human