Background Central precocious puberty (CPP) has been associated with loss-of-function mutations in two paternally expressed genes (MKRN3 and DLK1). Rare defects in the DLk1 were also associated with poor metabolic phenotype at adulthood. Objective Our aim was to investigate genetic and biochemical aspects of DLK1 in a Spanish cohort of children with CPP without MKRN3 mutations. Patients A large cohort of children with idiopathic CPP (Spanish PUBERE Registry) was studied. Genomic DNA was obtained from 444 individuals (168 index cases) with CPP and their close relatives. Automatic sequencing of MKRN3 and DLK1 genes were performed. Results Five rare heterozygous mutations of MKRN3 were initially excluded in girls with familial CPP. A rare allelic deletion (c.401_404+8del) in the splice site junction of DLK1 was identified in a Spanish girl with sporadic CPP. Pubertal signs started at 5.7 years. Her metabolic profile was normal. Familial segregation analysis showed that the DLK1 deletion was de novo in the affected child. Serum DLK1 levels were undetectable (A and g.-223 G>A) in two girls with CPP However, both had normal DLK1 serum levels. Conclusion Loss-of-function mutations of DLK1 represent a rare cause of CPP, reinforcing a significant role of this factor in human pubertal timing.

Single nucleotide variants (SNVs) are the most common type of genetic variation among humans. High-throughput sequencing methods have recently characterized millions of SNVs in several thousand individuals from various populations, most of which are benign ...

OBJECTIVES: High-throughput sequencing of genomes, exomes, and disease-focused gene panels is becoming increasingly common for molecular diagnostics. However, identifying a single clinically relevant pathogenic variant among thousands of genetic polymorphisms is a challenging task. Publicly available genomic databases are useful resources to filter out common genetic variants present in the population and enable the identification of each disease-causing variant. Based on our experience applying these technologies at Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP), [...] OBJECTIVES: High-throughput sequencing of genomes, exomes, and disease-focused gene panels is becoming increasingly common for molecular diagnostics. However, identifying a single clinically relevant pathogenic variant among thousands of genetic polymorphisms is a challenging task. Publicly available genomic databases are useful resources to filter out common genetic variants present in the population and enable the identification of each disease-causing variant. Based on our experience applying these technologies at Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP),

Several rare loss-of-function mutations of delta-like noncanonical notch ligand 1 (DLK1) have been described in non-syndromic children with familial central precocious puberty (CPP). We investigated genetic abnormalities of DLK1 gene in a French cohort of children with idiopathic CPP. Additionally, we explored the pattern of DLK1 serum levels in patients with CPP and in healthy children at puberty, as well as in wild-type female mice. Genomic DNA was obtained from 121 French index cases with CPP. Automated sequencing of the coding region of the DLK1 gene was performed in all cases. Serum DLK1 levels were measured by ELISA immunoassay in 209 individuals, including 191 with normal pubertal development and in female mice during postnatal pubertal maturation. We identified two rare pathogenic DLK1 allelic variants: a stop gain variant (c.372C > A; p.Cys124X) and a start loss variant (c.2T > G; p.Met1? , or p.0) in two French girls with CPP. Mean serum DLK1 levels were similar between healthy children and idiopathic CPP children. In healthy individuals, DLK1 levels correlated with pubertal stage: in girls, DLK1 decreased between Tanner stage III and V, whereas in boys, DLK1 decreased between Tanner stage II and V (p = 0.008 and 0.016, respectively). Serum levels of Dlk1 also decreased in wild-type female mice. Novel loss-of-function mutations in DLK1 gene were identified in two French girls with CPP. Additionally, we demonstrated a pattern of dynamic changes in circulating DLK1 serum levels in humans and mice during pubertal stages, reinforcing the role of this factor in pubertal timing.

Adrenocortical carcinoma (ACC) is a rare malignancy that is associated with a dismal prognosis. Pan-genomic studies have demonstrated the involvement of ATRX and ZNRF3 genes in adrenocortical tumorigenesis. Our aims were to evaluate the protein expression of ATRX and ZNRF3 in a cohort of 82 adults with ACC and to establish their prognostic value. Two pathologists analyzed immuno-stained slides of a tissue microarray. The low protein expression of ATRX and ZNRF3 was associated with a decrease in overall survival (OS) (p = 0.045, p = 0.012, respectively). The Cox regression for ATRX protein expression of >1.5 showed a hazard ratio (HR) for OS of 0.521 (95% CI 0.273–0.997; p = 0.049) when compared with ≤1.5; for ZNRF3 expression >2, the HR for OS was 0.441 (95% CI, 0.229–0.852; p = 0.015) when compared with ≤2. High ATRX and ZNRF3 protein expressions were associated with optimistic recurrence-free survival (RFS) (p = 0.027 and p = 0.005, respectively). The Cox regression of RFS showed an HR of 0.332 (95%CI, 0.111–0.932) for ATRX expression >2.7 (p = 0.037), and an HR of 0.333 (95%CI, 0.140–0.790) for ZNRF3 expression >2 (p = 0.013). In conclusion, low protein expression of ATRX and ZNRF3 are negative prognostic markers of ACC; however, different cohorts should be evaluated to validate these findings.

The etiology of central precocious puberty (CPP) has expanded with identification of new genetic causes, including the monogenic deficiency of MKRN3. We aimed to assess the prevalence of CPP causes and the predictors of genetic involvement in this phenotype. A retrospective cohort study for an etiological survey of patients with CPP from a single academic center. All patients with CPP had detailed medical history, phenotyping, and brain MRI; those with negative brain MRI (apparently idiopathic) were submitted to genetic studies, mainly DNA sequencing studies, genomic microarray, and methylation analysis. We assessed 270 patients with CPP; 50 (18.5%) had CPP-related brain lesions [34 (68%) congenital lesions]; whereas 220 had negative brain MRI. Of the latter, 174 (165 girls) were included for genetic studies. Genetic etiologies were identified in 22 patients (20 girls), indicating an overall frequency of genetic CPP of 12.6% (22.2% in boys and 12.1% in girls). The most common genetic defects were MKRN3, DLK1, and MECP2 loss-of-function mutations, followed by 14q32.2 defects (Temple syndrome). Univariate logistic regression identified family history (OR 3.3; 95%CI 1.3-8.3; p = 0.01) and neurodevelopmental disorders (OR 4.1; 95%CI 1.3-13.5; p = 0.02) as potential clinical predictors of genetic CPP. Distinct genetic causes were identified in 12.6% patients with apparently idiopathic CPP, revealing the genetic etiology as a relevant cause of CPP in both sexes. Family history and neurodevelopmental disorders were suggested as predictors of genetic CPP. We originally proposed an algorithm to investigate the etiology of CPP including genetic studies.