Original Research Article | Published:

Reproductive genetic carrier screening for cystic fibrosis, fragile X syndrome, and spinal muscular atrophy in Australia: outcomes of 12,000 tests

Genetics in Medicine volume 20, pages 513523 (2018) | Download Citation

  • A Correction to this article was published on 01 February 2018

Abstract

Purpose

To describe our experience of offering simultaneous genetic carrier screening for cystic fibrosis (CF), fragile X syndrome (FXS), and spinal muscular atrophy (SMA).

Methods

Carrier screening is offered through general practice, obstetrics, fertility, and genetics settings before or in early pregnancy. Carriers are offered genetic counseling with prenatal/preimplantation genetic diagnosis available to those at increased risk.

Results

Screening of 12,000 individuals revealed 610 carriers (5.08%; 1 in 20): 342 CF, 35 FXS, 241 SMA (8 carriers of 2 conditions), approximately 88% of whom had no family history. At least 94% of CF and SMA carriers’ partners were tested. Fifty couples (0.42%; 1 in 240) were at increased risk of having a child with one of the conditions (14 CF, 35 FXS, and 1 SMA) with 32 pregnant at the time of testing. Of these, 26 opted for prenatal diagnosis revealing 7 pregnancies affected (4 CF, 2 FXS, 1 SMA).

Conclusion

The combined affected pregnancy rate is comparable to the population risk for Down syndrome, emphasizing the need to routinely offer carrier screening. The availability of appropriate genetic counseling support and a collaborative approach between laboratory teams, genetics services, health professionals offering screening, and support organizations is essential.

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Acknowledgements

We acknowledge Cystic Fibrosis Victoria, Fragile X Alliance (Jonathan Cohen), Fragile X Association of Australia, and Spinal Muscular Atrophy Association of Australia (Julie Cini) for their encouragement and input into the development of this screening program. We thank the members of the original CF carrier screening program team (Martin Delatycki, Agnes Bankier, Lisette Curnow, Robin Forbes, Vicki Petrou, Liane Ioannou, Desirée du Sart, Steven Nasioulas, Melanie Smith, and John Massie). We also acknowledge the contribution of Deborah Dalton, Associate Genetic Counselor.

Author information

Author notes

    • Alison Dalton Archibald
    •  & Melanie Jane Smith

    Alison Dalton Archibald and Melanie Jane Smith are co-first authors.

Affiliations

  1. Victorian Clinical Genetics Services, Parkville, Victoria, Australia

    • Alison Dalton Archibald
    • , Melanie Jane Smith
    • , Trent Burgess
    • , Katrina Louise Scarff
    • , Justine Elliott
    • , Clare Elizabeth Hunt
    • , Caitlin Barns-Jenkins
    • , Chelsea Holt
    • , Karina Sandoval
    • , Vanessa Siva Kumar
    • , Lisa Ward
    • , Shannon Cowie
    • , David Francis
    • , Martin B Delatycki
    • , Mark Domenic Pertile
    • , Desirée du Sart
    • , Damien Bruno
    •  & David J Amor
  2. Murdoch Childrens Research Institute, Parkville, Victoria, Australia

    • Alison Dalton Archibald
    • , Melanie Jane Smith
    • , Trent Burgess
    • , Caitlin Barns-Jenkins
    • , Chelsea Holt
    • , Karina Sandoval
    • , Vanessa Siva Kumar
    • , Lisa Ward
    • , Emily Caroline Allen
    • , Sarah Valerie Collis
    • , David Francis
    • , Martin B Delatycki
    • , Eppie Mildred Yiu
    • , R John Massie
    • , Mark Domenic Pertile
    • , Desirée du Sart
    • , Damien Bruno
    •  & David J Amor
  3. Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia

    • Alison Dalton Archibald
    • , Trent Burgess
    • , Emily Caroline Allen
    • , Sarah Valerie Collis
    • , Martin B Delatycki
    • , Eppie Mildred Yiu
    • , R John Massie
    • , Mark Domenic Pertile
    • , Desirée du Sart
    • , Damien Bruno
    •  & David J Amor
  4. Royal Children’s Hospital, Parkville, Victoria, Australia

    • Martin B Delatycki
    • , Eppie Mildred Yiu
    • , R John Massie
    •  & David J Amor

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Competing interests

The authors declare no conflict of interest.

Corresponding author

Correspondence to Melanie Jane Smith.

Supplementary information

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Publication history

Received

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DOI

https://doi.org/10.1038/gim.2017.134

Supplementary material is linked to the online version of the paper at http://www.nature.com/gim

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