PROP1 Gene Analysis in Korean Children with Hypopituitarism

Abstract

Purpose: Mutations of the PROP1 (Prophet of PIT1) gene lead to combined pituitary hormone deficiency (CPHD), which is characterized by a deficiency of growth hormone (GH), thyroid stimulating hormone (TSH), luteinizing hormone (LH)/follicle stimulating hormone (FSH), prolactin (PRL) and adrenocorticotropic hormone (ACTH). We studied the PROP1 mutations in Korean children with hypopituitarism.

Methods: Twelve patients with congenital hypopituitarism were recruited from the Ajou University Hospital, Korea. The pituitary phenotype ranged from isolated growth hormone deficiency (IGHD) to CPHD. Clinical data, including endocrine and neuroradiological data were obtained from the medical records, and the DNA was collected and screened for mutations within PROP1 using polymerase chain reaction (PCR). The PCR products were sequenced directly.

Results: Nine patients had abnormal pituitary gland and three patients showed normal pituitary gland in magnetic resonance imaging (MRI). Endocrinologically, seven patients had IGHD and five had CPHD. Three of CPHD had GHD and hypogonadotrophic hypogonadism and the other two had GHD, central hypothyroidism, and ACTH deficiency. We identified no mutations in the PROP1 gene. However, three known polymorphisms were identified: The 27T→C (Ala9Ala) and the associated IVS1+3A→G in exon 1 were found in 25% of patient alleles sequenced. The 424G→A (Ala142Thr) in exon 3 change was identified in 4% of those sequenced.

Conclusion: This study corresponds to the previous reports that PROP1 mutations are rare in sporadic cases of CPHD. The low mutation frequency in Korean patients may be due to ethnic-specificity or other candidate genes causing this disease. It is necessary to study PROP1 gene and the involved genes in more Korean patients.