Role of GLI2 in hypopituitarism phenotype

Author(s)

Arnhold, Ivo J. P. ^[1] ; Franca, Marcela M. ^[1] ; Carvalho, Luciani R. ^[1] ; Mendonca, Berenice B. ^[1] ; Jorge, Alexander A. L. ^[2]

Affiliation

^[1] Univ Sao Paulo, Lab Hormonios & Genet Mol LIM 42, Hosp Clin FMUSP, Unidade Endocrinol Desenvolviment, Disciplina Endocrinol, Fac Med, Div Endocrinol, BR-05403900 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Unidade Endocrinol Genet, Lab Endocrinol Celular & Mol LIM 25, Disciplina Endocrinol, Fac Med, BR-01246903 Sao Paulo - Brazil

• Document type: Review article
• Source: JOURNAL OF MOLECULAR ENDOCRINOLOGY; v. 54, n. 3, p. R141-R150, JUN 2015.
• Web of Science Citations: 22

Abstract

GLI2 is a zinc-finger transcription factor involved in the Sonic Hedgehog pathway. Gli2 mutant mice have hypoplastic anterior and absent posterior pituitary glands. We reviewed the literature for patients with hypopituitarism and alterations in GLI2. Twenty-five patients (16 families) had heterozygous truncating mutations, and the phenotype frequently included GH deficiency, a small anterior pituitary lobe and an ectopic/undescended posterior pituitary lobe on magnetic resonance imaging and postaxial polydactyly. The inheritance pattern was autosomal dominant with incomplete penetrance and variable expressivity. The mutation was frequently inherited from an asymptomatic parent. Eleven patients had heterozygous non-synonymous GLI2 variants that were classified as variants of unknown significance, because they were either absent from or had a frequency lower than 0.001 in the databases. In these patients, the posterior pituitary was also ectopic, but none had polydactyly. A third group of variants found in patients with hypopituitarism were considered benign because their frequency was >= 0.001 in the databases. GLI2 is a large and polymorphic gene, and sequencing may identify variants whose interpretation may be difficult. Incomplete penetrance implies in the participation of other genetic and/or environmental factors. An interaction between Gli2 mutations and prenatal ethanol exposure has been demonstrated in mice dysmorphology. In conclusion, a relatively high frequency of GLI2 mutations and variants were identified in patients with congenital GH deficiency without other brain defects, and most of these patients presented with combined pituitary hormone deficiency and an ectopic posterior pituitary lobe. Future studies may clarify the relative role and frequency of GLI2 alterations in the aetiology of hypopituitarism. (AU)

• FAPESP's process: 13/03236-5 - New approaches and methodologies in molecular-genetic studies of growth and pubertal development disorders
• Grantee: Alexander Augusto de Lima Jorge
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 05/04726-0 - Molecular characterization of congenital endocrine diseases that affect growth and development
• Grantee: Ana Claudia Latronico Xavier
• Support Opportunities: Research Projects - Thematic Grants