Article

Massively parallel sequencing, ArrayCGH and RNA-Seq technologies provide a comprehensive molecular diagnosis of Fanconi anemia.

Cancer Genetics Branch, National Human Genome Research Institute, NIH, Bethesda, MD, United States
Blood (Impact Factor: 9.78). 04/2013; 121(22). DOI: 10.1182/blood-2012-12-474585
Source: PubMed

ABSTRACT Current methods for detecting mutations in Fanconi anemia (FA) suspected patients are inefficient and often miss mutations. We have applied recent advances in DNA sequencing and genomic capture to the diagnosis of FA. Specifically, we used custom Molecular Inversion Probes or TruSeq-enrichment oligos to capture and sequence FA and related genes, including introns, from 27 samples from the International Fanconi Anemia Registry at the Rockefeller University. DNA sequencing was complemented with custom Array Comparative Genomic Hybridization (aCGH) and RNA-Seq analysis. aCGH identified deletions/duplications in four different FA genes. RNA-Seq analysis revealed lack of allele specific expression associated with a deletion, and splicing defects caused by missense, synonymous, and deep-in-intron variants. The combination of TruSeq targeted capture, aCGH and RNA-Seq enabled us to identify the complementation group and biallelic germline mutations in all 27 families: FANCA (7), FANCB (3), FANCC (3), FANCD1 (1), FANCD2 (3), FANCF (2), FANCG (2), FANCI (1), FANCJ (2) and FANCL (3). FANCC mutations are often the cause of FA in patients of Ashkenazi Jewish (AJ) ancestry, and we identified two novel FANCC mutations in two patients of AJ ancestry. We describe here a strategy for efficient molecular diagnosis of Fanconi anemia.

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