Genetic Study of Insulin-Like Growth Factor-I Receptor Mutations in Patients With Intrauterine Growth Retardation

PROTOCOL OUTLINE:

Patients undergo blood draw. Insulin-like growth factor-I (IGF-I) and insulin-like growth
factor binding protein-3 (IGFBP-3) are measured. Patients whose IGF-I and IGFBP-3 levels are
average or above are tested for the presence of mutation in the insulin-like growth factor-I
receptor.

- Intrauterine growth retardation (IUGR), defined as birth weight less than 2 standard
deviations below the mean by Usher and McLean Deficient "catch-up" growth (stature
less than 5th percentile on growth chart after age 18 months) Normal or elevated
circulating concentrations of insulin-like growth factor-I (IGF-I) and insulin-like
growth factor binding protein-3 (IGFBP-3) IGF-I or IGFBP-3 within or above the 95th
percentile confidence interval for age No other clinical explanation for poor
prenatal and postnatal growth No IUGR due to maternal toxemia, endocrine disease,
gastrointestinal disease, significant heart disease, or chromosomal abnormalities No
other condition known to retard growth