hrp0082p1-d2-216 | Reproduction (1) | ESPE2014

IGSF1 Variants in Boys with Familial Delayed Puberty

Joustra Sjoerd , Wehkalampi Karoliina , Oostdijk Wilma , Biermasz Nienke , Howards Sasha , Bernard Daniel , Maarten Wit Jan , Dunkel Leo , Losekoot Monique

Background: The immunoglobulin superfamily member 1 (IGSF1) gene encodes a plasma membrane glycoprotein enriched in pituitary and testes. Loss-of-function mutations in IGSF1 cause an X-linked syndrome of central hypothyroidism (CeH), macroorchidism, and delayed pubertal rise of testosterone despite normal timing of testicular growth. This syndrome was discovered in patients with CeH; therefore, it is presently unknown whether IGSF1 mutations also cau...

hrp0082p1-d3-198 | Pituitary | ESPE2014

Spatial and Temporal Expression of Immunoglobulin Superfamily Member 1 in the Rat

Joustra Sjoerd , Meijer Onno , Oostdijk Wilma , Heinen Charlotte , Mol Isabel , Carreno Gabriela , Bernard Daniel , Biermasz Nienk , van Pelt Ans , Hamer Geert , Wit Jan Maarten , Wagenaar Gerry

Background: Loss-of-function of immunoglobulin superfamily member 1 (IGSF1) results in an X-linked syndrome of central hypothyroidism and macroorchidism, variable prolactin deficiency, GH deficiency, increased fat percentage, and delayed puberty testosterone rise despite normal timing of testicular growth.Methods: We investigated the spatial and temporal expression of IGSF1 at the protein and mRNA levels in fetal, neonatal, and adult Wistar rats, using i...

hrp0082p1-d2-217 | Reproduction (1) | ESPE2014

Reference Charts for Testicular Volume in Dutch Children and Adolescents

Joustra Sjoerd , van der Plas Evelyn , Goede Joery , Oostdijk Wilma , Delemarre - Van de Waal Henriette , Hack Wilfried , van Buuren Stef , Maarten Wit Jan

Background: Measurement of testicular volume is important when conditions associated with a delay or advance in the onset of puberty, or micro- and macroorchidism, are suspected. Measured testicular volumes must be compared with reference data, preferably expressed in S.D. curves using the LMS method, as is routinely done for many auxological measurements in pediatrics. The current study therefore aimed to construct LMS-smoothed age-reference charts for testicul...

hrp0084p1-81 | Growth Hormone | ESPE2015

The Growth Response to Growth Hormone Treatment is Greater in Patients with SHOX Enhancer Deletions Compared to SHOX Defects

Donze Stephany , Meijer Caroline , Kant Sarina , Zandwijken Gladys , van der Hout Annemieke , van Spaendonk Resie , van den Ouweland Ans , Wit Jan Maarten , Losekoot Monique , Oostdijk Wilma

Background: Short stature caused by point mutations or deletions of the short stature homeobox (SHOX) gene (SHOX haploinsufficiency, SHI) is a registered indication for growth hormone (GH) treatment. Patients with a SHOX enhancer deletion (SED) have a similar phenotype, but their response to GH is unknown. It is uncertain if duplications of SHOX or its enhancer (SDUP) can cause short stature.Objective and hypotheses: To describe the clinical characterist...

hrp0084p2-511 | Pituitary | ESPE2015

Pituitary Hormone Secretion Profiles in IGSF1 Deficiency Syndrome

Joustra Sjoerd , Roelfsema Ferdinand , Endert Eric , Ballieux Bart , van Trotsenburg Paul , Fliers Erik , Corssmit Noortje , Bernard Daniel , Oostdijk Wilma , Wit Jan Maarten , Pereira Alberto , Biermasz Nienke

Background: Loss-of-function of immunoglobulin superfamily, member 1 (IGSF1) causes an x-linked syndrome of central hypothyroidism, macroorchidism, delayed pubertal testosterone rise, variable prolactin deficiency, and variable partial growth hormone deficiency in childhood. The clinical features and gene expression pattern suggest a pivotal role for IGSF1 in the pituitary, but detailed knowledge on pituitary hormone secretion in this syndrome is lacking.<p class=...

hrp0086fc11.1 | Thyroid | ESPE2016

Mutations in TBL1X as a Novel Cause of Familial Central Hypothyroidism

Heinen Charlotte , Losekoot Monique , Sun Yu , Watson Peter , Fairall Louise , Joustra Sjoerd , Zwaveling-Soonawala Nitash , Oostdijk Wilma , van den Akker Erica , Santen Gijs , van Rijn Rick , Dreschler Wouter , Surovtseva Olga , Biermasz Nienke , Hennekam Raoul , Wit Jan , Schwabe John , Boelen Anita , Fliers Eric , van Trotsenburg Paul

Background: Congenital central hypothyroidism (CeH) may occur isolated, or in combination with other pituitary hormone deficiencies. Although a third causative gene for CeH was recently reported (IGSF1), the aetiology of isolated CeH has remained unexplained in most cases.Objective and hypotheses: We hypothesized that in three relatives with unexplained isolated CeH a mutation in another gene might be responsible for the phenotype.<p class="...