Nelly Pitteloud, M.D.

Professor of Medicine
Chief, Endocrinology, Diabetes, & Metabolism Service

Research Interests :

  • Human genetics
  • Hypogonadotropic hypogonadism (IHH - Kallmann syndrome)
  • GnRH neuron ontogeny
  • Fibroblast Growth Factor (FGF) signaling and associated diseases
  • Hypothalamic Amenorrhea (HA) & Polycystic Ovarian Syndrome (PCOS)
  • Metabolic disorders & insulin resistance
  • Diabetes & MODY

See complete CV 

Portrait - MedMag April 2024: read full article

Professor Pitteloud is a translational researcher focused on the neuroendocrine and gonadal control of human reproduction, GnRH neuron ontogeny, and the links between metabolism and reproduction. She spent 12 years in the United States conducting clinical research studies at the Massachusetts General Hospital and Harvard Medical School and is internationally recognized for her expertise in the genetics of human reproduction.

Her investigative approach is collaborative and multidisciplinary, spanning the fields of human genetics, molecular biology, and crystallography. Professor Pitteloud’s work delineating the molecular basis and phenotypic spectrum of GnRH deficiency has been published in leading scientific journals and has changed the field in several important ways :

  • demonstrating reversibility of congenital GnRH deficiency, a condition previously considered to be lifelong
  • introducing and expanding the concept of oligogenic causes of GnRH deficiency
  • identifying FGF8, a novel ligand in the FGF signaling pathway underlying GnRH deficiency, opening several new avenues of investigation
  • discovering a genetic basis for hypothalamic amenorrhea, a form of infertility previously thought to be caused only by environmental stressors


Genetics of Inherited Neuroendocrine Reproductive Disorders
This study aims to elucidate the genetic control of puberty and human reproduction. To learn more about this study or to refer a patient, please contact Nelly Pitteloud.

Characterizing the Reproductive and Metabolic Profiles of GnRH Deficient Patients
This project studies the phenotypic expression of GnRH disorders through detailed neuroendocrine profiling and metabolic assessments.

GnRH Deficeincy: Elucidation of the neuroendocrine control of human reproduction
This project creates a European consortium of clinicians, basic scientists, geneticists, and bioinformatics specialists interested in GnRH biology and reproduction. This network aims to create a patient registry, develop clinical best practices guidelines, provide patient support, facilitate collaboration, and train young investigators in the field. For more info see

FGF21 is a link between reproduction and energy balance
This interdisciplinary project involves leading investigators in the fields of human genetics, structural biology, chronobiology, and astrocytes metabolism to deepen our understanding of FGF21 biology and examine FGF21 as a link between energy metabolism, the neuroendocrine control of reproduction, and the circadian clock.

Role of FGF Signaling in the Neuroendocrine Control of Reproduction:
This study uses the complementary approaches of human genetics, murine studies, structural biology, and molecular biology to elucidate the biology of the FGF pathway including the FGF8 synexpression group.

Role of Rare Variants Underlying Common Reproductive Disorders:
This project examines the single gene disorders in ‘’maturity onset diabetes of the young’’ (MODY). Specifically it aims to discover new genes involved in the familial cases of MODY and better understand the variable expressivity of hyperglycemia within family members carrying the same gene defect.

European Cooperation in Science and Technology (COST): Building an international network of investigators studying the causes of GNRH deficiency
COST Action BM1105 is an international consortium of physicians and scientists studying hypogonadotropic hypogonadism, which is characterised by delayed or absent puberty, and infertility. This condition results from GnRH deficiency and is frequently associated with a lack of sense of smell (called Kallmann syndrome). This 4 year project aims to build a collaborative network that is actively seeking to involve patients, in order to translate scientific discoveries into improved patient care.

Group Members

James ACIERNO Jr, Research manager 
Daniele CASSATELLA, M.S. - Doctoral studentSee short CV
Andrew DWYER, R.N., F.N.P. - Project managerSee complete CV
Jenny MEYLAN MERLINI, Laborantine 
Emmanuel SOMM, M: D Ph.D 
Cheng XU, M.D.- PhD Student 


  • Swiss National Foundation Sinergia Grant: FGF21 is a link between reproduction and energy balance
  • Swiss National Foundation: The Neuroendocrine Control of Reproduction.
  • National Institutes of Health: Role of FGF Signaling in the Neuroendocrine Control of Reproduction.
  • European Cooperation in Science and Technology (COST): GnRH deficiency: Elucidation of the neuroendocrine control of human reproduction.
 Dernière mise à jour le 08/05/2024 à 09:54