Asuragen has been awarded a one-year, $346,000 grant from the National Institute of Child Health and Human Development to develop a high-throughput version of its PCR-based fragile X syndrome test for use in newborn population screening, according to a recently published grant abstract.
Under the grant, which began in late September, Asuragen plans to modify its test to enable direct amplification from the type of blood spot cards routinely used to collect blood samples from newborns to test for various disorders.
Fragile X is the most common form of inherited mental retardation, affecting roughly one in 4,000 males and one in 6,000 females, with carrier rates as high as one in 130 in females and one in 250 in males. The disease arises from expansion of a CGG trinucleotide sequence in the 5'-untranslated region of the FMR1 gene.
Asuragen's assay, called AmplideX FMR1, consists of optimized PCR reagents and methods to enable highly efficient amplification of the characteristic GC-rich DNA repeat mutations.
The Austin, Texas-based company has published several papers — including one landmark study published in March 2010 in Clinical Chemistry — demonstrating that its assay is faster, more accurate, and more sensitive than previous methods, and can detect very large expansion mutations previously only detectable using comparatively tedious and time-consuming Southern blot analysis (PCR Insider, 3/4/10).
In March of this year, Asuragen launched the AmplideX FMR1 PCR kit in Europe after receiving the CE Mark (PCR Insider, 3/24/11). The assay currently has research-use-only labeling in the US.
Nevertheless, Auragen still has designs on eventually implementing the AmplideX FMR1 assay in newborn population screening, and as such will use the NICHHD grant to support this effort.
According to the grant's abstract, specific aims of the project include optimizing procedures for blood spot processing with Whatman 903 paper; optimizing its FMR1 CGG repeat PCR reagents and subsequent capillary electrophoresis detection for use with processed blood spot card samples; and automating both blood spot processing and FMR1 PCR.
"The outcome of this research will be demonstrated feasibility for an accurate, automated, and cost-effective platform for fragile X detection in newborns, and address a longstanding unmet need for scalable technologies that can identify fragile X disorders in both males and females in the broader population," the grant's abstract states.
Other developers of molecular fragile X diagnostic assays include Quest Diagnostics, which in July won New York State regulatory approval allowing it to offer the test in New York and all other US states (PCR Insider, 7/29/10); and the ARUP Institute for Clinical and Experimental Pathology at the University of Utah, which used analyte-specific reagents made by Celera and distributed by Abbott to develop its own triple repeat-primed/capillary electrophoresis test with "laboratory-developed test" authorization under CLIA (PCR Insider, 5/20/10).
In June, Asuragen and collaborators at the University of California MIND Institute published research demonstrating the feasibility of a modified version of AmplideX FMR1 to determine the methylation status of the FMR1 gene and potentially further improve diagnosis of fragile X syndrome (PCR Insider, 6/30/11).