General information
The SALSA MLPA Probemix P185 Intersex is a research use only (RUO) assay for the detection of deletions or duplications in the NR0B1 (DAX1), SOX9, SRY, WNT4 and NR5A1 genes.

The sex-determining region on chromosome Y (SRY) is the most important sex-determining region in humans. As a transcriptional activator, the SRY protein’s main function is to initiate male sex determination by regulating a genetic switch in male development.

In addition to SRY, the dosage-sensitive sex reversal (DSS) gene, NR0B1 (also known as DAX1) has also been found to influence sex-determination. Duplication of the NR0B1 gene region, resulting in two active copies can override the testis-determining signal, resulting in the development of ovaries and an XY female. In testicular Sertoli and Leydig cells, NR0B1 can be up-regulated by WNT4.

The SOX9 gene functions as a critical Sertoli cell differentiation factor. SOX9 deletions, as well as chromosomal rearrangements such as deletions in an enhancer-containing region far upstream of SOX9 can lead to campomelic dysplasia with or without XY sex reversal (Leipoldt et al. 2007; Katoh-Fukui et al. 2015).

The NR5A1 gene encodes the orphan nuclear receptor steroidogenic factor-1 (SF1) which plays a key role in regulating adrenal and gonadal development, steroidogenesis and reproduction. Haploinsufficiency of NR5A1 has been described in several 46, XY individuals with mild gonadal dysgenesis and impaired androgenization, but normal adrenal function, suggesting that dosage-sensitive or domain-specific effects of SF1 action are important in human testicular development and function.

More information is available at https://www.ncbi.nlm.nih.gov/books/NBK1547/.

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 P185-C3 Intersex contains 45 MLPA probes with amplification products between 121 and 495 nucleotides (nt). This includes probes for the following genes: NR0B1 (DAX1) and CXorf21 (TASL) on Xp21.2, SOX9 on 17q24.3, SRY, UTY and ZFY on Yp11.21-31, WNT4 on 1p36.12 and NR5A1 on 9q33.3. Furthermore, flanking probes specific for the X chromosome are included. 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.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.