POU1F1, also known as POU Class 1 Homeobox1, is a pituitary-specific transcription factor. It plays a crucial role in the development and function of the anterior pituitary gland, regulating the expression of genes encoding growth hormone (GH), thyroid-stimulating hormone (TSH), and prolactin [1,2,3]. Mutations in POU1F1 can lead to combined pituitary hormone deficiency, highlighting its importance in normal pituitary function [1,2,3,4]. Genetic mouse models are valuable for studying its functions.

Mice carrying the Pou1f1 c.143-83A>G substitution, mimicking a human intronic variant, showed postnatal growth failure, anterior pituitary hypoplasia, and deficiencies in circulating insulin-like growth factor 1 and thyroxine. RNA-seq and immunohistochemical analyses revealed a reduction in somatotrophs. Reverse transcription polymerase chain reaction showed abnormal splicing in homozygous mice, with changes in the levels of alpha and beta isoforms of Pou1f1 and the emergence of an exon-skipped transcript [2]. In humans, POU1F1 mutations are prevalent in Indian combined pituitary hormone deficiency (CPHD) cohorts. Different mutation types are associated with varying phenotypes, and patients with heterozygous mutations tend to have milder phenotypes compared to those with homozygous or compound heterozygous mutations [1]. Some patients with POU1F1 mutations may present with central precocious puberty or early puberty, although the genotype-phenotype relationship is not yet firmly established [3].

In conclusion, POU1F1 is essential for the proper development and function of the anterior pituitary gland, regulating the production of key hormones. The study of POU1F1 using mouse models, especially those with specific mutations, has provided insights into its role in growth, pituitary development, and the occurrence of diseases such as combined pituitary hormone deficiency and associated puberty-related disorders [1,2,3].