General information: The SALSA MLPA Probemix P156 GALT is a research use only (RUO) assay for the detection of deletions or duplications in the GALT gene, which is associated with Classic Galactosemia and Clinical Variant Galactosemia.

Classic galactosemia and clinical variant galactosemia are disorders of the galactose metabolism inherited in an autosomal recessive manner. These disorders are caused by defects of the GALT gene, encoding galactose-1-phosphate uridylyltransferase. Failure to thrive is the most common initial clinical symptom of galactosemia. The cardinal features of these disorders are hepatomegaly, cataracts, and intellectual disability. After exclusion of galactose from the diet, these signs and symptoms normalise. Classic galactosemia is estimated to occur 1 in 30,000 to 60,000 newborns, while the prevalence for the clinical variant galactosemia is unknown. Some cases of clinical variant galactosemia might be missed during the newborn screening, since breath testing is normal and hypergalactosemia is not as marked as in the classic galactosemia.

The GALT gene has 11 exons, spans ~4.0 kb of genomic DNA, and is located on chromosome 9p13.3, about 35 Mb from the p-telomere.

More information is available at https://www.ncbi.nlm.nih.gov/books/NBK1518/.

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 P156-B3 GALT contains 22 MLPA probes with amplification products between 140 and 337 nucleotides (nt). This includes 11 probes covering all the exons of the GALT gene, one probe for the DNAI1 gene located upstream of GALT gene, and one probe for the downstream IL11RA gene. In addition, nine 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.mlpa.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.mlpa.com.