DCC/NTN1 complex mutations in patients with congenital hypogonadotropic hypogonadism impair GnRH neuron development

Abstract

Congenital hypogonadotropic hypogonadism (CHH) is a rare genetic disease characterized by absent puberty and infertility due to GnRH deficiency, and is often associated with anosmia [Kallmann syndrome (KS)]. The genetic etiology of CHH is heterogeneous, and more than 30 genes have been implicated in approximately 50% of patients with CHH. We hypothesized that genes encoding axon-guidance proteins containing fibronectin type-III (FN3) domains (similar to ANOS1, the first gene associated with KS), are mutated in CHH. We performed whole-exome sequencing in a cohort of 133 CHH probands to test this hypothesis, and identified rare sequence variants (RSVs) in genes encoding for the FN3-domain encoding protein deleted in colorectal cancer (DCC) and its ligand Netrin-1 (NTN1). In vitro studies of these RSVs revealed altered intracellular signaling associated with defects in cell morphology, and confirmed five heterozygous DCC mutations in 6 probands-5 of which presented as KS. Two KS probands carry heterozygous mutations in both DCC and NTN1 consistent with oligogenic inheritance. Further, we show that Netrin-1 promotes migration in immortalized GnRH neurons (GN11 cells). This study implicates DCC and NTN1 mutations in the pathophysiology of CHH consistent with the role of these two genes in the ontogeny of GnRH neurons in mice.

Characterization of the human GnRH neuron developmental transcriptome using a GNRH1-TdTomato reporter line in human pluripotent stem cells

“…4A), including the genes associated with both KS (i.e. anosmic phenotype) and normosmic CHH (Boehm et al, 2015;Bouilly et al, 2018;Howard et al, 2016;Xu et al, 2017;Richards et al, 2017;Kotan et al, 2018). We found 15 validated CHH genes differentially expressed in D27TdT + versus D20FGF8 (Fig.…”

“…4B). Netrin 1 (NTN1) and its receptor deleted in colorectal cancer (DCC) are known to be involved in GnRH neuron migration during embryonic development, and DCC expression has been reported in GnRH neurons (Low et al, 2012;Bouilly et al, 2018;Schwarting et al, 2004). Also plexin-A1 (PLXNA1), receptor of class 3 Fig.…”

The Clinical and Genetic Characteristics of Chinese Male Pediatric Patients With Congenital Hypogonadotropic Hypogonadism

“…In 2015, the European CHH consensus summarized 31 pathogenic genes, including X-chromosome-linked recessive, autosomal recessive, and dominant genes [1]. At present, more than 90 candidate genes may be involved in the pathogenesis of CHH, and some newly reported genes have been con rmed in CHH patients; some genes involved in GnRH neuronal migration and axon formation in animal models have not been con rmed in CHH patients [7,[9][10][11][12][13][14][15]. In our previous study, only 10 pathogenic genes were con rmed in CHH patients [8].…”

Novel Microdeletion in the X Chromosome Leads to Kallmann Syndrome, Ichthyosis, Obesity, and Strabismus

“…Gene mutations that are only present in KS probands include ANOS1 (alias KAL1), SOX10, SEMA3A, FEZF1, DUSP6, RMST, and NDNF (Miraoui et al, 2013;Messina et al, 2020;Stamou et al, 2020). Genes that can cause both KS and nIHH include FGFR1, NSMF, PROK2, PROKR2, CHD7, FGF8, WDR11, HS6ST1, FGF17, IL17RD, SPRY4, FLRT3, SEMA7A, AXL, SEMA3E, PLXNA1, KLB, NTN1, DCC, and AMHR2 (Abreu et al, 2008;Canto et al, 2009;Miraoui et al, 2013;Stamou et al, 2016;Marcos et al, 2017;Xu et al, 2017;Bouilly et al, 2018;Maione et al, 2018;Malone et al, 2019;Young et al, 2019). Mutations in TUBB3 and PTCH1 may also cause syndromic diseases including KS (Mitchell et al, 2011;Barraud et al, 2020).…”