👤 Jan Cools

17β-Hydroxysteroid dehydrogenase 3 deficiency (17β-HSDD) and 5α-reductase type 2 deficiency (5α-RD) are rare 46,XY differences of sex development (DSD). This study aims to enlarge the limited knowledge on long-term gonadal function and gonadal pathology in these conditions. Retrospective multicentre cohort study. Data on phenotype, laboratory results, and hormone treatment were collected from patients aged ≥16 years at time of data collection with genetically confirmed 17β-HSDD and 5α-RD from 10 centres via the I-DSD Registry. If gonadectomy or gonadal biopsy had been performed, pathology reports and/or gonadal tissue or images were collected. All 16 patients with 17β-HSDD were raised female; 1 (6%) changed to male gender at age 14. Three females were treated with gonadotrophin-releasing hormone agonists (GnRHa) to prevent virilisation. Thirteen underwent gonadectomy at median age 8 (range 0-17). None had germ cell (pre)malignancies. Of 14 patients with 5α-RD, 10 (71%) were raised female. Five changed gender at age 7-23, of whom 4 to male gender. One was treated with GnRHa. Six underwent gonadectomy at median age 10 (range 0-31). None had germ cell (pre)malignancies. With gonads in situ, puberty spontaneously progressed. Three were treated with dihydrotestosterone. A significant percentage of individuals with 17β-HSDD and 5α-RD changed gender, and some were treated with GnRHa to prevent virilisation before making a definitive decision about gonadectomy. When left in situ, spontaneous puberty occurs and germ cell (pre)malignancies seem uncommon at least until early adulthood. Together, these data support delaying a decision about gonadectomy until late adolescence in these conditions. Show less

RNA-seq is a promising technology to re-sequence protein coding genes for the identification of single nucleotide variants (SNV), while simultaneously obtaining information on structural variations and gene expression perturbations. We asked whether RNA-seq is suitable for the detection of driver mutations in T-cell acute lymphoblastic leukemia (T-ALL). These leukemias are caused by a combination of gene fusions, over-expression of transcription factors and cooperative point mutations in oncogenes and tumor suppressor genes. We analyzed 31 T-ALL patient samples and 18 T-ALL cell lines by high-coverage paired-end RNA-seq. First, we optimized the detection of SNVs in RNA-seq data by comparing the results with exome re-sequencing data. We identified known driver genes with recurrent protein altering variations, as well as several new candidates including H3F3A, PTK2B, and STAT5B. Next, we determined accurate gene expression levels from the RNA-seq data through normalizations and batch effect removal, and used these to classify patients into T-ALL subtypes. Finally, we detected gene fusions, of which several can explain the over-expression of key driver genes such as TLX1, PLAG1, LMO1, or NKX2-1; and others result in novel fusion transcripts encoding activated kinases (SSBP2-FER and TPM3-JAK2) or involving MLLT10. In conclusion, we present novel analysis pipelines for variant calling, variant filtering, and expression normalization on RNA-seq data, and successfully applied these for the detection of translocations, point mutations, INDELs, exon-skipping events, and expression perturbations in T-ALL. Show less