Ester W A, Hokken-Koelega A C S
Department of Paediatrics, Division of Endocrinology, Erasmus MC-Sophia Children's Hospital, Rotterdam, The Netherlands.
Best Pract Res Clin Endocrinol Metab. 2008 Jun;22(3):415-31. doi: 10.1016/j.beem.2008.03.001.
Small for gestational age (SGA) is the term used to describe a group of children born with a birth weight and/or birth length below the normal range of a reference population, corrected for their gestational age. Although animal models have shown that insulin-like growth factor 1 (IGF1) and insulin-like growth factor 1 receptor (IGF1R) genes are important candidates for reduced pre- and postnatal growth, only limited case reports have been published describing mutations. This might suggest that IGF1 and IGF1R are such crucial growth factors that only common genetic polymorphisms are allowed to survive. Common IGF1 and IGF1R gene polymorphisms, such as single nucleotide polymorphisms and variable number of tandem repeats, have been investigated with conflicting results with respect to SGA-related outcomes. The exact contribution of these polymorphisms to clinical practice remains to be elucidated.
小于胎龄儿（SGA）是用于描述一组出生体重和/或出生身长低于参考人群正常范围（根据其胎龄校正）的儿童的术语。尽管动物模型表明胰岛素样生长因子1（IGF1）和胰岛素样生长因子1受体（IGF1R）基因是出生前后生长减缓的重要候选基因，但仅有有限的病例报告描述了相关突变。这可能表明IGF1和IGF1R是如此关键的生长因子，以至于只有常见的基因多态性能够留存。常见的IGF1和IGF1R基因多态性，如单核苷酸多态性和串联重复序列可变数目，针对与SGA相关的结局进行了研究，结果相互矛盾。这些多态性对临床实践的确切贡献仍有待阐明。
