Kallmann syndrome deletion of the short arm of chromosome 8
Joana Guimarães, Margarida Bastos, Leonor Gomes, Miguel Melo & Manuela Carvalheiro
Introduction: Kallmann Syndrome (KS) consists of hypogonadotropic hypogonadism and anosmia, and is 5 fold more prevalent in males. There is a considerable clinical and genetic heterogeneity and a crescent interest in autosomal genes. The FGFR1 gene, located on the short arm of chromossome 8, encodes a glycoprotein fibroblast growth factor receptor and FGFR1 mutations has been identified in 10% of KS patients. The clinical picture include typical KS and associated features.
Case study: A female, 30 years old, with primary amenorrhea, short statue (P5P10), cleft palate, hyposmia, mental retardation and right hearing loss. Laboratory evaluation showed hypoganodotropic hypogonadism, an GnRH stimulation test showed a probable hypothalamic origin of the hypogonadism (IGF-1, GH, FT3, FT4, TSH and cortisol were normal). The pelvic ultrasonography was normal and MRI showed a lipoma of the III ventricle and agenesis of the corpus callosum. Analysis of G-banded prometaphase chromosomes from lymphocyte cultures showed a deletion on the short arm of chromosome 8: 46,XX,del(8)(p12-pter).
Conclusion: We present a patient with an 8p12-pter deletion, agenesis of the corpus callosum, cleft palate, mental retardation, right hearing loss in association with Kallmann syndrome phenotype. There are rare cases describe in literature with this associations. These findings suggest that autosomal genes are important for KS and we have to pay attention to other features associated with KS phenotype.