Postnatal overgrowth by 15q-trisomy and intrauterine growth retardation by 15q-monosomy due to familial translocation t(13;15): dosage effect of IGF1R?
We report a 4-year-old boy, a 6-month-old girl, and a 17-week-old fetus all with a chromosomal imbalance derived from a balanced translocation t(13;15)(q34;q26.1) of their father. The boy had a partial trisomy for 15q26.1-qter (46,XY,der(13)t(13;15)(q34;q26.1)) and postnatal overgrowth, as well as craniosynostosis, facial anomalies, and finger joint contractures, while the girl with the same chromosomal aberration did not show overgrowth, although she had similar craniofacial and skeletal abnormalities. The fetus had a partial monosomy for 15q26.1-qter and intrauterine growth retardation (IUGR). Fluorescence in situ hybridization (FISH) analysis with a BAC clone covering the insulin-like growth factor 1 receptor gene (IGF1R) that is located to 15q25-q26 revealed three copies in the boy, one copy in the fetus, and two copies in their phenotypically normal father. Since deletion of IGF1Rhas repeatedly been reported to be associated with IUGR, it is tempting to speculate that the dosage of IGF1R may have determined growth in these children.
Nagai
Toshiro
T
Department of Pediatrics, Dokkyo University School of Medicine, Koshigaya Hospital, Saitama, Japan. t-nagai@dokkyomed.ac.jp
Shimokawa
Osamu
O
Harada
Naoki
N
Sakazume
Satoru
S
Ohashi
Hirofumi
H
Matsumoto
Naomichi
N
Obata
Kazuo
K
Yoshino
Atsunori
A
Murakami
Nobuyuki
N
Murai
Takayasu
T
Sakuta
Ryoichi
R
Niikawa
Norio
N
D000028:Abortion, Induced; D002675:Child, Preschool; D002882:Chromosomes, Human, Pair 13 / Q000235:genetics*; D002884:Chromosomes, Human, Pair 15 / Q000235:genetics*; D005192:Family Health; D017809:Fatal Outcome; D005260:Female; D005317:Fetal Growth Retardation / Q000235:genetics* / Q000473:pathology; D018628:Gene Dosage; D006130:Growth Disorders / Q000235:genetics* / Q000473:pathology; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D008297:Male; D009006:Monosomy; D010375:Pedigree; D017526:Receptor, IGF Type 1 / Q000235:genetics; D014178:Translocation, Genetic; D014314:Trisomy
D017526:Receptor, IGF Type 1