For Healthcare Professionals:

About the Genetic Obesity ID (GO-ID) Initiative

We invite you to participate in Genetic Obesity ID (GO-ID), focused on improving the diagnosis and understanding of obesity resulting from either POMC (pro-opiomelanocortin) or LepR (leptin receptor) deficiency—two rare but important types of genetic, early-onset obesity.

POMC Deficiency and LepR Deficiency
POMCdeficiency obesity is characterized by severe, early-onset obesity, hyperphagia, and often adrenal insufficiency from corticotropin (ACTH) deficiency. Weight gain continues rapidly, so that by the end of the first year of life, obesity is severe (weight generally well above the 98th percentile for age, without increased height). Red hair and Fitzpatrick type 1 skin (which burns but never tans) are common, but not invariable. On occasion, central hypothyroidism from TSH deficiency, adolescent-onset GH deficiency, and adolescent-onset hypogonadotropic hypogonadism from FSH deficiency can also be seen.1 In addition, POMC-deficient patients with PCSK1 mutations may also exhibit a history of diarrhea or malabsorption in infancy.

LepR deficiency obesity is also characterized by severe, early-onset obesity and hyperphagia. In addition, patients homozygous for this mutation have impaired pubertal development and their secretion of growth hormone and thyrotropin is reduced.2

How You Can Participate
You can participate in either or both of the following programs:

  1. GO-ID PATIENT REGISTRATION: A database of confirmed POMC- and LepR-deficient patients
  2. GO-ID GENOTYPING STUDY: An IRB-approved genetic screening study for individuals suspected of POMC- or LEPR-deficiency obesity

POMC-deficiency obesity and LepR-deficiency obesity are exceptionally rare. We believe, however, that the prevalence of these disorders is underestimated. The goal of the Patient Registration is to identify patients worldwide with a confirmed diagnosis of these genetic disorders, and the Genotyping Study is under way to screen undiagnosed people for these serious, often life-threatening, diseases. It is our hope that through more careful study, we will gain a better understanding of the true prevalence of POMC- and LEPR-deficiency obesity and the spectrum of their clinical presentations, thus allowing for earlier diagnosis and more targeted medical management.

Recent studies suggest that POMC and LepR-deficiency obesity are distinct syndromes that may be clinically identifiable and uniquely responsive to therapies aimed at the underlying POMC and LepR gene defects (and also including PCSK1 mutations as another gene defect implicated in POMC-deficiency obesity). Thus, this genotyping study also has the potential for identifying children and adults who might benefit from ongoing research into these conditions.

If you have any questions, please do not hesitate to contact us:

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We look forward to hearing from you.

1 Challis BG, Millington GWM. Proopiomelanocortin Deficiency. GeneReviews. December 13, 2013.
2 Clément L, Vaisse C, Lahlou N, Cabrolk s, Pelloux V, Cassuto D, Gourmelenk M, Dina C, Chambaz J, Lacorte JM, Basdevant A, Bougnères P, Lebouck Y, Froguel P, Guy-Grand B. A Mutation in the Human Leptin Receptor Gene Causes Obesity and Pituitary Dysfunction.Nature. 1998; (392): 398-401.

The GO-ID Genotyping study is supported by a grant from Rhythm.


The GO-ID Genotyping Study is supported by a grant from Rhythm Pharmaceuticals, Inc. The content on this site is intended for use by patients, caregivers, and healthcare professionals for informational purposes only and is not intended to be taken as medical advice.
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