Premature thelarche from phenotype to genotype.
1Institute of Maternal and Child Research, (IDIMI), School of Medicine, University of Chile, Casilla 226-3, Santiago, Chile. ecodner@med.uchile.cl
Pediatric Endocrinology Reviews : PER
|March 28, 2008
Summary
Premature thelarche (PT) is a benign condition of early breast development. Some cases, termed exaggerated thelarche, may involve GNAS gene mutations and represent a state between PT and precocious puberty.
Area of Science:
- Pediatric endocrinology
- Genetics
- Reproductive health
Background:
- Premature thelarche (PT) is a benign condition often seen in infancy.
- It is characterized by early breast development, sometimes with elevated estrogen levels and increased growth velocity.
- Exaggerated thelarche is a subtype that may bridge PT and precocious puberty.
Purpose of the Study:
- To discuss the phenotypes associated with premature thelarche.
- To explore the various etiologies of premature thelarche.
- To highlight recent findings on genetic factors, including GNAS mutations.
Main Methods:
- Review of clinical presentations of premature thelarche.
- Analysis of hormonal profiles, including estrogen and gonadotropins.
- Genetic analysis for mutations in relevant genes, such as GNAS.
Main Results:
- Premature thelarche is a common variant of puberty, prevalent in the first year of life.
- Ultrasensitive assays show higher estrogen levels in girls with PT.
- Some cases of exaggerated thelarche show GNAS gene mutations.
Conclusions:
- Premature thelarche encompasses a spectrum of presentations.
- Etiologies include endocrine disruptors, genetic, and nutritional factors.
- GNAS gene mutations are implicated in some cases of exaggerated thelarche.
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