RESUMO
Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare severe cutaneous adverse reactions to drugs. Granulysin (GNLY) plays a key role in keratinocyte apoptosis during SJS/TEN pathophysiology. To determine if GNLY-encoding mutations might be related to the protein's functional disturbances, contributing to SJS/TEN pathogenesis, we performed direct sequencing of GNLY's coding region in a group of 19 Colombian SJS/TEN patients. A GNLY genetic screening was implemented in a group of 249 healthy individuals. We identified the c.11G > A heterozygous sequence variant in a TEN case, which creates a premature termination codon (PTC) (p.Trp4Ter). We show that a mutant protein is synthesised, possibly due to a PTC-readthrough mechanism. Functional assays demonstrated that the mutant protein was abnormally located in the nuclear compartment, potentially leading to a toxic effect. Our results argue in favour of GNLY non-synonymous sequence variants contributing to SJS/TEN pathophysiology, thereby constituting a promising, clinically useful molecular biomarker.
Assuntos
Antígenos de Diferenciação de Linfócitos T/genética , Queratinócitos/patologia , Proteínas Mutantes/metabolismo , Mutação , Necrose , Síndrome de Stevens-Johnson/genética , Síndrome de Stevens-Johnson/patologia , Adolescente , Adulto , Apoptose , Biomarcadores/metabolismo , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Proteínas Mutantes/genética , Adulto JovemRESUMO
OBJECTIVE: To identify new molecular actors involved in nonsyndromic premature ovarian failure (POF) etiology. DESIGN: This is a retrospective case-control cohort study. SETTING: University research group and IVF medical center. PATIENT(S): Twelve women affected by nonsyndromic POF. The control group included 176 women whose menopause had occurred after age 50 and had no antecedents regarding gynecological disease. A further 345 women from the same ethnic origin (general population group) were also recruited to assess allele frequency for potentially deleterious sequence variants. INTERVENTION(S): Next generation sequencing (NGS), Sanger sequencing, and bioinformatics analysis. MAIN OUTCOME MEASURE(S): The complete coding regions of 70 candidate genes were massively sequenced, via NGS, in POF patients. Bioinformatics and genetics were used to confirm NGS results and to identify potential sequence variants related to the disease pathogenesis. RESULT(S): We have identified mutations in two novel genes, ADAMTS19 and BMPR2, that are potentially related to POF origin. LHCGR mutations, which might have contributed to the phenotype, were also detected. CONCLUSION(S): We thus recommend NGS as a powerful tool for identifying new molecular actors in POF and for future diagnostic/prognostic purposes.