Rosa Vargas-Poussou1, Lamisse Mansour-Hendili1, Stéphanie Baron1, Jean-Philippe Bertocchio1, Caroline Travers1, Christophe Simian1, Cyrielle Treard1, Véronique Baudouin1, Sonia Beltran1, Françoise Broux1, Odile Camard1, Sylvie Cloarec1, Catherine Cormier1, Xavier Debussche1, Emmanuelle Dubosclard1, Celine Eid1, Jean-Philippe Haymann1, Soto Romuald Kiando1, Jean-Marc Kuhn1, Guy Lefort1, Agnes Linglart1, Bernadette Lucas-Pouliquen1, Marie-Alice Macher1, Gérard Maruani1, Sophie Ouzounian1, Michel Polak1, Elisabeth Requeda1, Dominique Robier1, Caroline Silve1, Jean-Claude Souberbielle1, Ivan Tack1, Delphine Vezzosi1, Xavier Jeunemaitre1, Pascal Houillier1. 1. Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou (R.V.-P., L.M.-H., C.Tra., C.Sim., C.Tre., X.J.), Service de Génétique, Paris, France; INSERM, UMR970 (R.V.-P., L.M.-H., C.Tre., S.R.K., X.J.), Paris-Centre de Recherche Cardiovasculaire, Paris, France; Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (R.V.-P., J.-P.B., V.B., M.-A.M., X.J., P.H.), Paris, France; Faculté de Médecine (L.M.-H., S.Bar., J.-P.B., X.J., P.H.), Université Paris Descartes, Paris, France; Département de Physiologie (S.Bar., J.-P.B., G.M., P.H.), Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Paris, France; Service de Néphrologie (V.B., M.-A.M.), Assistance Publique-Hôpitaux de Paris, Hôpital Robert Debré, Paris, France; Service d'Endocrinologie (S.Bel.), Centre Hospitalier de Vienne, Vienne, France; Département de Pédiatrie (F.B.), Centre Hospitalier Universitaire de Rouen, Rouen, France; Service de Pédiatrie (O.C., D.R.), Centre Hospitalier de Niort, Niort, France; Département de Néphrologie (S.C.), Centre Hospitalier Universitaire de Tours, Tours, France; Département de Rhumatologie A (C.C.), Assistance Publique-Hôpitaux de Paris, Hôpital Cochin, Paris, France; Service d'endocrinologie (X.D.), Centre hospitalier Felix Guyon, St Denis de la Réunion, France; Service de Médicine Interne (E.D.), Centre Hospitalier Henri Mondor d'Aurillac, Aurillac, France; Service d'Endocrinologie (C.D.), Centre Hospitalier de Perpignan, Perpignan, France; Département de Physiologie (J.-P.H.), Assistance Publique-Hôpitaux de Paris, Hôpital Tenon, Paris, France; Département d'Endocrinologie (J.-M.K.), Centre Hospitalier Universitaire de Rouen, Rouen, France; Service d'Endocrinologie (G.L.), Centre Hospitalier de Niort, Niort, France; Assistance Publique-Hôpitaux de Paris, Service d'Endocrinologie Pédiatrique (A.L.), Hôpital Kremlin Bicêtre, Le Kremlin-Bicêtre, France; Service d'Endocrinologie
Abstract
CONTEXT: Familial hypocalciuric hypercalcemia (FHH) is a genetically heterogeneous condition resembling primary hyperparathyroidism (PHPT) but not curable by surgery; FHH types 1, 2, and 3 are due to loss-of-function mutations of the CASR, GNA11, or AP2S1 genes, respectively. OBJECTIVE: This study aimed to compare the phenotypes of patients with genetically proven FHH types 1 or 3 or PHPT. DESIGN, SETTING, AND PATIENTS: This was a mutation analysis in a large cohort, a cross-sectional comparison of 52 patients with FHH type 1, 22 patients with FHH type 3, 60 with PHPT, and 24 normal adults. INTERVENTION: There were no interventions. MAIN OUTCOME MEASURES: Abnormalities of the CASR, GNA11, and AP2S1 genes, blood calcium, phosphate, and PTH concentrations, urinary calcium excretion were measured. RESULTS: In 133 families, we detected 101 mutations in the CASR gene, 68 of which were previously unknown, and in 19 families, the three recurrent AP2S1 mutations. No mutation was detected in the GNA11 gene. Patients with FHH type 3 had higher plasma calcium concentrations than patients with FHH type 1, despite having similar PTH concentrations and urinary calcium excretion. Renal tubular calcium reabsorption levels were higher in patients with FHH type 3 than in those with FHH type 1. Plasma calcium concentration was higher whereas PTH concentration and urinary calcium excretion were lower in FHH patients than in PHPT patients. In patients with FHH or PHPT, all data groups partially overlapped. CONCLUSION: In our population, AP2S1 mutations affect calcium homeostasis more severely than CASR mutations. Due to overlap, the risk of confusion between FHH and PHPT is high.
CONTEXT: Familial hypocalciuric hypercalcemia (FHH) is a genetically heterogeneous condition resembling primary hyperparathyroidism (PHPT) but not curable by surgery; FHH types 1, 2, and 3 are due to loss-of-function mutations of the CASR, GNA11, or AP2S1 genes, respectively. OBJECTIVE: This study aimed to compare the phenotypes of patients with genetically proven FHH types 1 or 3 or PHPT. DESIGN, SETTING, AND PATIENTS: This was a mutation analysis in a large cohort, a cross-sectional comparison of 52 patients with FHH type 1, 22 patients with FHH type 3, 60 with PHPT, and 24 normal adults. INTERVENTION: There were no interventions. MAIN OUTCOME MEASURES: Abnormalities of the CASR, GNA11, and AP2S1 genes, blood calcium, phosphate, and PTH concentrations, urinary calcium excretion were measured. RESULTS: In 133 families, we detected 101 mutations in the CASR gene, 68 of which were previously unknown, and in 19 families, the three recurrent AP2S1 mutations. No mutation was detected in the GNA11 gene. Patients with FHH type 3 had higher plasma calcium concentrations than patients with FHH type 1, despite having similar PTH concentrations and urinary calcium excretion. Renal tubular calcium reabsorption levels were higher in patients with FHH type 3 than in those with FHH type 1. Plasma calcium concentration was higher whereas PTH concentration and urinary calcium excretion were lower in FHHpatients than in PHPT patients. In patients with FHH or PHPT, all data groups partially overlapped. CONCLUSION: In our population, AP2S1 mutations affect calcium homeostasis more severely than CASR mutations. Due to overlap, the risk of confusion between FHH and PHPT is high.
Authors: Katie Leach; Fadil M Hannan; Tracy M Josephs; Andrew N Keller; Thor C Møller; Donald T Ward; Enikö Kallay; Rebecca S Mason; Rajesh V Thakker; Daniela Riccardi; Arthur D Conigrave; Hans Bräuner-Osborne Journal: Pharmacol Rev Date: 2020-07 Impact factor: 25.468
Authors: Shafaq Khairi; Jenae Osborne; Michelle F Jacobs; Gregory T Clines; Barbra S Miller; David T Hughes; Tobias Else Journal: Horm Cancer Date: 2020-08-05 Impact factor: 3.869
Authors: Fadil M Hannan; Mark Stevenson; Asha L Bayliss; Victoria J Stokes; Michelle Stewart; Kreepa G Kooblall; Caroline M Gorvin; Gemma Codner; Lydia Teboul; Sara Wells; Rajesh V Thakker Journal: Hum Mol Genet Date: 2021-05-29 Impact factor: 6.150