Genetic counselling problems with parents of child with ROB der(21;21)(q10:q10) Down syndrome: a case report
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Abstract
Background
Down syndrome (DS) is a genetic disorder caused by addition of a full or partial chromosome 21. The most common type of DS (90–95%) is pure trisomy 21; mosaicism occurs in 6–7%, and about 3–5% comprises translocation DS including Robertsonian translocation, which could be inherited from parents. This case shows a Robertsonian translocation der(21;21)(q10:q10) DS and the common financial problem among Indonesian parents being their inability to pay for examinations to determine the origin of the abnormality (inherited or de novo), which is a big challenge for genetic counselors.
Case Description
A 2-month-old baby boy was admitted to the hospital with suspect Down syndrome referred by a pediatrician. The patient was the only child of 25-year-old parents. Physical examination showed several characteristics of DS, including upslanting palpebral fissure, a flat nasal bridge, horizontal palmar creases, sandal gap, and continuous murmur in upper left sternal border due to patent ductus arteriosus. Cytogenetic testing revealed the karyotype of derivative chromosome 21, namely Robertsonian translocation 46,XY,+21,der(21;21)(q10:q10). Parents declined to order cytogenetic testing due to financial concerns.
Conclusion
Parents’ karyotype is critical to confirm the origin of the translocation. It is important to calculate the recurrence risk correctly especially when parents still want another child and to do non-directive counseling in terms of reproductive options. However, it cannot be done in this case because of the lack of parent’s karyotypes. Genetic counseling plays an essential role in providing an accurate recurrence risk based on the type of trisomy for future offspring and reproductive planning.
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References
1. Pal A, Daley SF. Down syndrome. Treasure Island (FL): StatPearls Publishing; 2026.
2. Anil V, Anirban M. De novo Robertsonian translocation t(21;21) in a child with Down syndrome. J Nepal Paediatr Soc 2017;37:92-4. https://doi.org/10.3126/jnps.v37i1.16184.
3. Karan V, Rosemary I, Kayla M, Preshon P, Alexander F, Mary M. Disparities and outcomes of patients living with Down syndrome undergoing healthcare transitions from pediatric to adult care: a scoping review. Am J Med Genet A 2022;1882293-2302. https://doi.org/10.1002/ajmg.a.62854.
4. Lu W, Zhou J, Rao H, et al. A retrospective analysis of Robertsonian translocations from a single center in China. Reprod Sci 2024;31:851–6. doi: 10.1007/s43032-023-01398-3.
5. Zhang S, Lei C, Wu J, et al. Meiotic heterogeneity of trivalent structure and interchromosomal effect in blastocysts with Robertsonian translocations. Front Genet 2021;12:609563. doi:10.3389/fgene.2021.609563.
6. Song J, Li X, Sun L, et al. A family with Robertsonian translocation: a potential mechanism of speciation in humans. Mol Cytogenet 2016;9:48. doi: 10.1186/s13039-016-0255-7.
7. Kalpana VL, Gowri Sai Ram PVV, Soujanya P, Anuradha A, Papa Kusuma B, Uma Bharati H. Robertsonian translocations t(21q;21q) and t(14q;21q) in Down syndrome. Int J Med Res Health Sci 2017;6:53-8.
8. Maya I, Sukenik-Halevy R, Basel-Salmon L, Sagi-Dain L. Ten points to consider when providing genetic counseling for variants of incomplete penetrance and variable expressivity detected in a prenatal setting. Acta Obstet Gynecol Scand 2020;99:1427-9. doi: 10.1111/aogs.13963.
9. Kusre G, Sarma M, Nirmolia T, Shankarishan P. Robertsonian translocation t(21; 21) in a female born to normal parents: a case report. J Clin Diagn Res 2015;9:GD01-2. doi: 10.7860/JCDR/2015/10638.5372.
10. Kolgeci S, Azemi M, Ahmeti H, Dervishi Z, Sopjani M, Kolgeci J. Recurrent abortions and Down syndrome resulting from Robertsonian translocation 21q; 21q. Med Arch 2012;66:350-2. doi: 10.5455/medarh.
11. Kollurage DUA, Kudagammana ST. Down syndrome caused by 21;21 Robertsonian translocation. Sri Lanka J Med 2018;27:43-5. doi:10.4038/sljm.v27i2.85.
12. Nikfar A, Mansouri M, Fatemi Abhari G. A rare de novo Robertsonian translocation t(21q;21q) in an Iranian child with Down syndrome: a case report. Acta Med Iran 2019;57:522-4. doi:10.18502/acta.v57i8.2430.
13. Van Steen K, Laird NM, Markel P, Molenberghs G. Approaches to handling incomplete data in family-based association testing. Ann Hum Genet 2007;71(Pt 2):141-51. doi: 10.1111/j.1469-1809.2006.00325.x.
14. Harris A, Bather JR, Bradshaw RL. Incomplete family history and meeting algorithmic criteria for genetic evaluation of hereditary cancer. JAMA Netw Open 2025;8:e2539870. doi: 10.1001/jamanetworkopen.2025.39870.
15. Mai CT, Isenburg JL, Canfield MA, et al. National population-based estimates for major birth defects, 2010-2014. Birth Defects Res 2019;111:1420-35. doi: 10.1002/bdr2.1589.
16. Priya PK, Mishra VV, Roy P, Patel H. A study on balanced chromosomal translocations in couples with recurrent pregnancy loss. J Hum Reprod Sci 2018;11:337-42. doi: 10.4103/jhrs.JHRS_132_17.
17. Wiland E, Olszewska M, Woźniak T, Kurpisz M. How much, if anything, do we know about sperm chromosomes of Robertsonian translocation carriers? Cell Mol Life Sci 2020;77:4765–85. doi:10.1007/s00018-020-03560-5.
18. Crellin E, Martyn M, McClaren B, et al. What matters to parents? A scoping review of parents’ service experiences and needs regarding genetic testing for rare diseases. Eur J Hum Genet 2023;31:869–78. doi: 10.1038/s41431-023-01376-y.
19. Miller EG, Young JL, Rao A, Ward-Lev E, Halley MC. Demographic characteristics associated with perceptions of personal utility in genetic and genomic testing: a systematic review. JAMA Netw Open 2023;6:e2310367. doi: 10.1001/jamanetworkopen.2023.10367.
20. Higgs E, Wain KE, Wynn J, et al. Measuring quality and value in genetic counseling: the current landscape and future directions. J Genet Couns 2023;32:315-24. doi: 10.1002/jgc4.1657.