Functional aspects of genetic variability in the GH genomic region.
Because of the small differences among genotypes, it would be difficult in basal conditions to detect the effect of genetic polymorphism in endocrine function, but this could emerge during provocative tests. We have studied four polymorphic sites of the GH gene region (17q24.2), MSPIA, MSPIB, BGLIIA, and BGLIIB. Gene and haplotype distributions in classes of growth retardation have been studied. The outcome of GH diagnostic test in relation to GH region genotypes has been evaluated by the analysis of area under the GH secretory curve. Ninety-eight growth retarded children have been studied. On the basis of provocative GH test these children were classified as total GH deficit (TD), partial GH deficit (PD), and familial short stature (FSS) with no deficit of GH. Sixty-three healthy controls were also considered. An increased frequency of MSPIA*2 allele in PD and TD as compared with FSS children and controls has been observed suggesting that this allele is associated with a decreased GH release. BGLIIA*2 allele appears decreased in PD and TD as compared with FSS and controls, suggesting that this allele is associated with an increased release of GH. Carriers of MSPIA*2 allele show a lower GH release as compared with MSPIA *1/*1 subjects on the provocative test by insulin, while carriers of BGLIIA*2 allele show a higher GH release as compared with BGLIIA *1/*1 subjects on the provocative test by clonidine. The functional aspects of genetic variability within the GH genomic area parallel the genetic differences observed between TD and PD versus FSS and control children.
Gloria-Bottini
F
F
Division of Biopathology of Human Population and Environmental Pathology, Department of Biopathology and Imaging Diagnostics, School of Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy. gloria@med.uniroma2.it
Amante
A
A
Lucarelli
P
P
Saccucci
P
P
Martinoli
R
R
Bottini
E
E
D000483:Alleles; D019540:Area Under Curve; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D003000:Clonidine; D006130:Growth Disorders / Q000145:classification / Q000235:genetics* / Q000503:physiopathology; D013006:Growth Hormone / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism; D006239:Haplotypes; D006801:Humans; D007004:Hypoglycemic Agents; D007328:Insulin; D007558:Italy; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D017027:Protein Tyrosine Phosphatases / Q000235:genetics; D011518:Proto-Oncogene Proteins / Q000235:genetics; D013268:Stimulation, Chemical; D013565:Sympatholytics
D007004:Hypoglycemic Agents; D007328:Insulin; D011518:Proto-Oncogene Proteins; D013565:Sympatholytics; D013006:Growth Hormone; C490429:ACP1 protein, human; D017027:Protein Tyrosine Phosphatases; D003000:Clonidine