Abstract

BackgroundSmall copy number variations confined to the placenta are extremely rare findings in chorionic villus sampling, nonetheless of great clinical importance. To the best of our knowledge, this is the first reported case of confined placental mosaicism for an intragenic Duchenne muscular dystrophy (DMD) gene deletion.Case presentationWe describe a pregnant woman where confined placental mosaicism for an intragenic DMD deletion was detected. She was referred for a chorionic villus sampling due to an increased risk of trisomy 21 derived from combined first trimester screening. Rapid aneuploidy detection showed a male fetus with normal results for chromosomes 13, 18 and 21. A chromosomal microarray demonstrated a deletion of exons 61–62 in the DMD gene in approximately 50% of the cells. A follow-up analysis on amniotic cells showed a normal result for the DMD gene. Hence, confined placental mosaicism was confirmed.ConclusionsWe propose tissue specific fragile sites as a possible theoretical mechanism for the formation of submicroscopic copy number variations and highlight that the finding of DMD deletion mosaicism in a chorionic villus sample might be isolated to the placenta. Therefore, confirmation by amniocentesis is of crucial clinical importance to avoid misdiagnosis of the fetus.

Highlights

  • Small copy number variations confined to the placenta are extremely rare findings in chorionic villus sampling, of great clinical importance

  • We propose tissue specific fragile sites as a possible theoretical mechanism for the formation of submicroscopic copy number variations and highlight that the finding of Duchenne muscular dystrophy (DMD) deletion mosaicism in a chorionic villus sample might be isolated to the placenta

  • Confirmation by amniocentesis is of crucial clinical importance to avoid misdiagnosis of the fetus

Read more

Summary

Conclusions

We propose tissue specific fragile sites as a possible theoretical mechanism for the formation of submicroscopic copy number variations and highlight that the finding of DMD deletion mosaicism in a chorionic villus sample might be isolated to the placenta.

Findings
Background
Discussion and conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call