The gene encoding human low-molecular weight insulin-like growth-factor binding protein (IGF-BP25): regional localization to 7p12-p13 and description of a DNA polymorphism.
The low-molecular weight insulin-like growth-factor binding protein (IGF-BP25) is synthesized by human liver, secretory endometrium and decidua, and is also present in human serum. It binds insulin-like growth factors IGF-I and IGF-II with high affinity, and is proposed to act as a paracrine regulator of cell growth. In situ hybridization studies with a cDNA encompassing the entire protein coding region of IGF-BP25 localized the gene to bands p12-p13 on chromosome 7. Southern blot analysis with the enzyme BglII revealed a common restriction fragment length polymorphism: the presence of the polymorphic BglII site results in the formation of two fragments 4.6 kb and 1.6 kb in size whereas its absence produces a single 6.2 kb fragment. The frequencies of the two alleles were 0.73 and 0.27, respectively. IGF-BP25 constitutes a useful genetic marker for the proximal short arm of chromosome 7.
Alitalo
T
T
Department of Medical Genetics, University of Helsinki, Finland.
Kontula
K
K
Koistinen
R
R
Aalto-Setälä
K
K
Julkunen
M
M
Jänne
O A
OA
Seppälä
M
M
de la Chapelle
A
A
D015139:Blotting, Southern; D002352:Carrier Proteins / Q000235:genetics*; D002871:Chromosome Banding; D002874:Chromosome Mapping; D002897:Chromosomes, Human, Pair 7; D004247:DNA / Q000235:genetics*; D015342:DNA Probes; D006801:Humans; D018969:Insulin-Like Growth Factor Binding Proteins; D012150:Polymorphism, Restriction Fragment Length
D002352:Carrier Proteins; D015342:DNA Probes; D018969:Insulin-Like Growth Factor Binding Proteins; D004247:DNA