RESUMEN
De novo germline variants in several components of the SWI/SNF-like BAF complex can cause Coffin-Siris syndrome (CSS), Nicolaides-Baraitser syndrome (NCBRS), and nonsyndromic intellectual disability. We screened 63 patients with a clinical diagnosis of CSS for these genes (ARID1A, ARID1B, SMARCA2, SMARCA4, SMARCB1, and SMARCE1) and identified pathogenic variants in 45 (71%) patients. We found a high proportion of variants in ARID1B (68%). All four pathogenic variants in ARID1A appeared to be mosaic. By using all variants from the Exome Variant Server as test data, we were able to classify variants in ARID1A, ARID1B, and SMARCB1 reliably as being pathogenic or nonpathogenic. For SMARCA2, SMARCA4, and SMARCE1 several variants in the EVS remained unclassified, underlining the importance of parental testing. We have entered all variant and clinical information in LOVD-powered databases to facilitate further genotype-phenotype correlations, as these will become increasingly important because of the uptake of targeted and untargeted next generation sequencing in diagnostics. The emerging phenotype-genotype correlation is that SMARCB1 patients have the most marked physical phenotype and severe cognitive and growth delay. The variability in phenotype seems most marked in ARID1A and ARID1B patients. Distal limbs anomalies are most marked in ARID1A patients and least in SMARCB1 patients. Numbers are small however, and larger series are needed to confirm this correlation.
Asunto(s)
Anomalías Múltiples/diagnóstico , Anomalías Múltiples/genética , Cara/anomalías , Estudios de Asociación Genética , Deformidades Congénitas de la Mano/diagnóstico , Deformidades Congénitas de la Mano/genética , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/genética , Micrognatismo/diagnóstico , Micrognatismo/genética , Complejos Multiproteicos/genética , Cuello/anomalías , Proteínas Cromosómicas no Histona/genética , ADN Helicasas/genética , Proteínas de Unión al ADN/genética , Exones , Facies , Orden Génico , Humanos , Proteínas Nucleares/genética , Fenotipo , Proteína SMARCB1 , Factores de Transcripción/genéticaRESUMEN
Differentiating primary endometrioid or mucinous ovarian tumors from secondary ovarian tumors can be challenging. We compared somatic mutation profiles of primary and secondary ovarian cancers to investigate if these profiles can help diagnose ovarian tumors. Cancer-related genes (n = 115) were screened by target-enriched next-generation sequencing in formalin-fixed, paraffin-embedded tumor tissue from 43 primary endometrioid and mucinous ovarian carcinomas and 28 proven colorectal cancer metastases to the ovary. Results were validated by high-resolution melting curve analysis and Sanger sequencing. TP53, NOTCH1, PIK3CA, and FAT4 versus APC, TP53, KRAS, and FAT4 mutations were the most common in the primary ovarian tumors and ovarian colorectal cancer metastases, respectively. An inactivating APC mutation was found in 4.7% of primary ovarian tumors (2 of 43; 95% CI, 1.6%-10.9%). In contrast, inactivating APC mutations were identified in 71% of colorectal cancer metastases (20 of 28; 95% CI, 55%-88%) (P < 0.001; sensitivity: 71.4%, 95% CI, 51.1%-86.0%; specificity: 95.4%, 95% CI, 82.9%-99.1%). Loss of heterozygosity and APC promoter hypermethylation did not differ significantly between the primary and secondary ovarian tumors. NOTCH1 mutations were observed specifically in primary ovarian tumors, although at a low frequency, but not in metastases (6 of 41; 14.6%; 95% CI, 3.8%-25.4%). APC mutation analysis can be used to differentiate primary endometrioid and mucinous ovarian tumors from colorectal cancer metastases to the ovary.