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Published Online: 1 February 2017

Design and Validation of a New MLPA-Based Assay for the Detection of RS1 Gene Deletions and Application in a Large Family with X-Linked Juvenile Retinoschisis

Publication: Genetic Testing and Molecular Biomarkers
Volume 21, Issue Number 2


Aims: X-linked juvenile retinoschisis (XLRS) is a severe ocular disorder that can evolve to blindness. More than 200 different disease-causing mutations have been reported in the RS1 gene and approximately 10% of these are deletions. Since transmission is X-linked, males are always affected and females are usually carriers. The identification of female carriers is always important and poses a technical challenge. Therefore, we sought to develop a multiplex ligation dependent probe amplification (MLPA)-based method to identify deletions or duplications in this gene. We then used our assay to study a large XLRS family.
Methods: We designed six probes specific for each RS1 exon and then optimized and validated our method using control samples with known gene deletions. In the XLRS family, RS1 gene copy number variation was assessed by “home-made” MLPA analysis and by single nucleotide polymorphism (SNP) array analysis using the CytoScan HD Array. Direct sequencing was used for deletion breakpoint mapping.
Results: Our assay detected all deletions in control samples. All affected males of the family were positive for a deletion of exon 2 of the RS1 gene (RS1:NM_000330:c.53-?_78+?del). Carrier females were also identified.
Conclusion: Our method is easily replicated, reliable, and inexpensive and allows female carriers to be detected. This is the first report of deep characterization of a whole exon deletion in the RS1 gene.

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Bowles K, Cukras C, Turriff A, et al. (2011) X-linked retinoschisis: RS1 mutation severity and age affect the ERG phenotype in a cohort of 68 affected male subjects. Invest Ophthalmol Vis Sci 52:9250–9256.
Chan WM, Choy KW, Wang J, et al. (2004) Two cases of X-linked juvenile retinoschisis with different optical coherence tomography findings and RS1 gene mutations. Clin Exp Ophthalmol 32:429–432.
D'Souza L, Cukras C, Antolik C, et al. (2013) Characterization of novel RS1 exonic deletions in juvenile X-linked retinoschisis. Mol Vis 19:2209–2216.
George ND, Yates JR, Moore AT (1995) X linked retinoschisis. Br J Ophthalmol 79:697–702.
George ND, Yates JR, Moore AT (1996) Clinical features in affected males with X-linked retinoschisis. Arch Ophthalmol 14:274–280.
Khan NW, Jamison JA, Kemp JA, Sieving PA (2001) Analysis of photoreceptor function and inner retinal activity in juvenile X-linked retinoschisis. Vision Res 41:3931–3942.
Kim DY, Mukai S (2013) X-linked juvenile retinoschisis (XLRS): a review of genotype-phenotype relationships. Semin Ophthalmol 28:392–396.
Mendoza-Londono R, Hiriyanna KT, Bingham EL, et al. (1999) A Colombian family with X-linked juvenile retinoschisis with three affected females finding of a frameshift mutation. Ophthalmic Genet 20:37–43.
Saldana M, Thompson J, Monk E, et al. (2007) X-linked retinoschisis in a female with a heterozygous RS1 missense mutation. Am J Med Genet A 143A:608–609.
Sellner LN, Taylor GR (2004) MLPA and MAPH: new techniques for detection of gene deletions. Hum Mutat 23:413–419.
Sikkink SK, Biswas S, Parry NR, et al. (2007) X-linked retinoschisis: an update. J Med Genet 44:225–232.
The Retinoschisis Consortium (1998) Functional implications of the spectrum of mutations found in 234 cases with X-linked juvenile retinoschisis. Hum Mol Genet 7:1185–1192.
Thiele H, Nürnberg P (2005) HaploPainter: a tool for drawing pedigrees with complex haplotypes. Bioinformatics 21:1730–1732.

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Published In

cover image Genetic Testing and Molecular Biomarkers
Genetic Testing and Molecular Biomarkers
Volume 21Issue Number 2February 2017
Pages: 116 - 121
PubMed: 27997221


Published in print: February 2017
Published online: 1 February 2017
Published ahead of print: 20 December 2016


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    Annalisa Nicoletti
    MAGI Non-Profit Human Medical Genetics Institute, Rovereto, Trento, Italy.
    Department of Medical and Surgical Sciences (DIMEC), University of Bologna, Bologna, Italy.
    Lucia Ziccardi
    “G.B. Bietti” Foundation—IRCCS, Roma, Italy.
    Paolo Enrico Maltese
    MAGI Non-Profit Human Medical Genetics Institute, Rovereto, Trento, Italy.
    Sabrina Benedetti
    MAGI Non-Profit Human Medical Genetics Institute, Rovereto, Trento, Italy.
    Orazio Palumbo
    Medical Genetics Service, “IRCCS Casa Sollievo della Sofferenza,” San Giovanni Rotondo, Italy.
    Michelina Rendina
    Medical Genetics Service, “IRCCS Casa Sollievo della Sofferenza,” San Giovanni Rotondo, Italy.
    Leonardo D'Agruma
    Medical Genetics Service, “IRCCS Casa Sollievo della Sofferenza,” San Giovanni Rotondo, Italy.
    Benedetto Falsini
    Institute of Ophthalmology, Policlinico Gemelli, Catholic University, Roma, Italy.
    Xinjing Wang
    DNA Diagnostic Laboratory, Ophthalmic Genetics and Visual Function Branch, National Eye Institute/NIH, Bethesda, Maryland.
    Matteo Bertelli
    MAGI Non-Profit Human Medical Genetics Institute, Rovereto, Trento, Italy.


    Address correspondence to:Paolo Enrico Maltese, PhDMAGI Non-Profit Human Medical Genetics InstituteRoveretoTrentoItaly
    E-mail: [email protected]

    Author Disclosure Statement

    No competing financial interests exist.

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