RESUMO
The efficacy and treatment outcome of a CML patient are heavily dependent on BCR::ABL1 kinase domain (KD) mutation status. Next-generation sequencing technology is a bright alternative to the previously used sanger sequencing method due to its global presence in diagnostic setups, massive parallel sequencing ability, and far better sensitivity. In the present study, we have demonstrated a new protocol for kinase domain mutation analysis using the next-generation sequencing (NGS) method using the ion torrent sequencing platform. This protocol uses RNA as the starting material, followed by nested PCR to amplify the fusion transcript, which is subsequently used as a template for NGS. Initial validation and comparison of this assay with the sanger sequencing (SS) method yielded 95.23% agreement. CML samples (n = 121) with a failure to TKI response were subjected to this newly developed NGS-based assay to detect KD mutations, from which samples were found to have mutations with a sensitivity ranging from 2.32 to 93.41%. A total of 34.71% of samples (n = 42) were found to be positive for one or more KD mutations, whereas 65.29% of samples (n = 81) were found to be negative. Nine samples out of 42 positive samples, i.e., 21.42%, were found to have compound mutations. This is one of the first studies from India, which includes more than 160 samples and is analyzed by the NGS approach for KD mutation analysis.
Assuntos
Proteínas de Fusão bcr-abl , Sequenciamento de Nucleotídeos em Larga Escala , Leucemia Mielogênica Crônica BCR-ABL Positiva , Mutação , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Estudos de Coortes , Análise Mutacional de DNA/métodos , Proteínas de Fusão bcr-abl/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Índia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Inibidores de Proteínas Quinases/uso terapêuticoRESUMO
This graphic abstract combines pedigree, dysmorphology features, radiographs, and the PRKG2 protein domain, specifically the CNB-A regulatory domain, which harbors a mutation resulting in premature protein termination.
Assuntos
Exoma , Família , Humanos , Proteína Quinase Dependente de GMP Cíclico Tipo II/genética , Exoma/genética , Mutação/genética , LinhagemRESUMO
Alazami syndrome (ALAZS) (MIM 615071) is a rare autosomal recessive disorder characterized by short stature, dysmorphic facial features, developmental delay, and impaired intellect. It was first reported in a Saudi Arabian family in 2012. Three Indian patients affected with ALAZS, one boy aged 13 years and other two sisters in their 40s are presented. These patients had few unreported dysmorphic facial features: high arched eyebrows and dental overcrowding. No microcephaly was noted in the sisters. One of the sisters did not have short stature. The boy also presented with unilateral buphthalmos of left eye. All three of them have been identified to harbor novel variants in LARP7.
Assuntos
Deficiências do Desenvolvimento/genética , Nanismo/genética , Deficiência Intelectual/genética , Ribonucleoproteínas/genética , Adolescente , Adulto , Deficiências do Desenvolvimento/patologia , Nanismo/patologia , Feminino , Predisposição Genética para Doença , Humanos , Índia/epidemiologia , Deficiência Intelectual/patologia , Masculino , Fenótipo , Irmãos , Adulto JovemRESUMO
Rett syndrome (RTT) is an X-linked disorder caused by mutations in MECP2 in majority of cases. It is characterized by arrested development between 6 and 18 months of age, regression of acquired hand skills and speech, stereotypic hand movements, gait abnormalities and seizures. There are a very few studies in India which illustrates mutation spectrum in RTT. None of the studies have correlated seizures with the genotype. This study describes the phenotype and genotype spectrum in children with RTT syndrome and analyses the association of epilepsy with various clinical features and molecular findings. All children with RTT in our cohort had global developmental delay. Genetic diagnosis identified mutations of the MECP2 in all 25 children where RTT was suspected. We have identified point mutations in 20 patients, one insertion and four deletions by Sanger sequencing, namely c.1164_1207 (44 bp), c.1165_1207 (43 bp), c.1157_1197 (41 bp) del and c.1157_1188 (32 bp). Clinically, none of the patients with deletion had seizures. We identified one novel insertion variant c.337_338 (p.S113Ffs*9). All the deletions were located in the C-terminal region. Majority of the mutations (22/25) were identified in exon 4 which comprised of nonsense and missense types. Screening of hotspot mutations in exon 4 should be the first line evaluation in diagnosis of RTT. Molecular testing could help in specific management of seizures in RTT.
