General information
The SALSA MLPA Probemix P457 DHCR7 is a research use only (RUO) assay for the detection of deletions or duplications in the DHCR7 gene, which is associated with the Smith-Lemli-Opitz syndrome (SLOS).

SLOS is an autosomal recessive syndrome, phenotypically characterized by mental retardation, facial dysmorphism, syndactyly of second and third toes, and holoprosencephaly. Defects in the DHCR7 gene, localised on chromosome 11q13, are the main cause of SLOS (Jira et al. 2003). The protein encoded by this gene is 7-dehydrocholesterol reductase, which plays a catalyser role in the final step of cholesterol biosynthesis. Therefore, the defects in the DHCR7 gene result in an abnormality in cholesterol metabolism. These defects are in its majority point mutations, although a few deletions have also been identified to cause SLOS (Waterham et al. 2012). The incidence of SLOS is of about 1:55,000 in North America, while in Central Europe it is significantly higher (~ 1:15,000) (Nowaczyk et al. 2006).

More information is available at https://www.ncbi.nlm.nih.gov/books/NBK1143/.

This SALSA MLPA probemix is not CE/FDA registered for use in diagnostic procedures. Purchase of this product includes a limited license for research purposes.

Probemix content
The SALSA MLPA Probemix P457-A3 DHCR7 contains 23 MLPA probes with amplification products between 148 and 318 nucleotides (nt). This includes eleven probes for the DHCR7 gene. In addition, 12 reference probes are included that detect autosomal chromosomal locations. Complete probe sequences and the identity of the genes detected by the reference probes are available online (www.mrcholland.com).

This probemix contains nine quality control fragments generating amplification products between 64 and 105 nt: four DNA Quantity fragments (Q-fragments), two DNA Denaturation fragments (D-fragments), one Benchmark fragment, and one chromosome X and one chromosome Y-specific fragment. More information on how to interpret observations on these control fragments can be found in the MLPA General Protocol and online at www.mrcholland.com.