E-ISSN 1858-8360 | ISSN 0256-4408
 

Short Communication 


SUDANESE JOURNAL OF PAEDIATRICS

2019; Vol 19, Issue No. 1

SHORT COMMUNICATION

Karyotype analysis in children with idiopathic intellectual disability

Hüseyin Çaksen (1), Hayrettin Okut (2), Mevlit İkbal (3)

(1) Department of Pediatric Neurology and Pediatric Genetics, Meram Medical Faculty, Necmettin Erbakan University, Meram Konya, Turkey

(2) Department of Biometry and Genetics, Faculty of Agricultural, Yüzüncü Yıl University, Van, Turkey

(3) Department of Medical Genetics, Faculty of Medicine, Karadeniz Technical University, Trabzon, Turkey

Correspondence to:

Huseyin Caksen

Department of Pediatrics, Meram Medical Faculty, Necmettin Erbakan University, Konya, Turkey

Email: huseyincaksen [at] hotmail.com

Received: 01 November 2018 | Accepted: 07 April 2019

How to cite this article:

Çaksen H, Okut H, İkbal M. Karyotype analysis in children with idiopathic intellectual disability. Sudan J Paediatr. 2019;19(1):57–59.

https://doi.org/10.24911/SJP.106-1539963785


ABSTRACT

Intellectual disability (ID) is a heterogeneous condition, affecting 1–3% of general population. In this study, karyotype analysis was performed in 33 children with idiopathic ID in a hospital with limited laboratory facilities to determine the value of karyotype analysis as a first step test in children with idiopathic ID. Thirty-three patients with idiopathic ID were included in the study. Giemsa-trypsin-Leishman (GTL) banding karyotype resolution at a standard resolution of 550 bands was performed to determine whether the patients had microdeletion/microduplication by using of conventional karyotype analysis. Of 33 children, seven (21.2%) showed various chromosomal changes. Polymorphisms including 46,XX,1qh+; 46,XX,1qh+,1qh+; 46,X,add(Y),q12; 46,XY,21ps+ and 46,XX,1qh+ were diagnosed in five children. Inversion [46,XY,inv9(p12q13)] and inversion and polymorphisms [46,XY,inv9(p12q13),13ps+] were diagnosed in two children, respectively. We believe that inv(9)(p12q13) is a benign variant. In conclusion, our findings showed that the karyotype analysis was not helpful to determine etiology in children with idiopathic ID, probably because of the low patient number in our study.


KEYWORDS

Idiopathic intellectual disability; Chromosomal analysis; Child


INTRODUCTION

Intellectual disability (ID) is a heterogeneous condition, affecting 1–3% of general population [1]. Based on the evidence to date, a standard karyotype, fragile X molecular genetic testing, array comparative genomic hybridisation (aCGH) and neuroimaging are performed in patients in whom an etiologic diagnosis is not suspected after the history and physical examinations. However, one can expect rapid changes in the microarray technology in the near future [2].

In the present study, karyotype analysis was performed in 33 children with idiopathic ID in a hospital with limited laboratory facilities to determine the value of karyotype analysis as a first step test in children with idiopathic ID.


MATERIALS AND METHODS

This study has been performed at Yüzüncü Yıl University, Faculty of Medicine, Department of Pediatric Neurology, Turkey. Thirty-three children with idiopathic ID, who had not major dysmorphic signs, or an underlying neurological or metabolic disorder leading to ID, were included in the study.

The patients’ demographical data were noted and a detailed physical examination was performed in all the patients. Porteus Labirents test for performance intelligence quotient (IQ) and Kent EGY test for verbal performance IQ were used in patients over 6 years. IQ was predicted based on clinical observations and information taken from parents in younger than 6 years and non-cooperative patients. In order to detect etiology of ID, serum thyroid function tests, tandem-mass spectrometry and cranial magnetic resonance imaging were performed in all the patients. Urinary organic acid analysis, urinary-blood amino acid levels, investigations for TORCH infections and cranial computerised tomography were examined in required patients. Giemsa-trypsin-Leishman (GTL) banding karyotype resolution at a standard resolution of 550 bands was performed to determine whether the patients had microdeletion/microduplication by using conventional karyotype analysis. The study was approved by Ethics Committee of Erciyes University Faculty of Medicine. A written consent was received from the patients’ parents.


RESULTS

Of 33 patients, 21 (63.6%) were males and 12 (36.4%) were females. Male/female ratio was 1.75. The mean age of patients was 4.25 ± 2.47 years (2.5–17 years). There was consanguinity between the parents of 10 (30.3%) patients. Three (9.0%) patients had severe ID, 15 (45.5%) had moderate ID and another 15 had mild ID. In addition to ID, 12 (36.3%) patients had epilepsy and motor retardation, 9 (27.2%) had motor retardation and 9 (27.2%) had epilepsy. No additional disorder was detected in the remaining three (9.0%) patients.

Of 33 children, seven (21.2%) showed various chromosomal changes. Polymorphisms including 46,XX,1qh+; 46,XX,1qh+,1qh+; 46,X,add(Y),q12; 46,XY,21ps+ and 46,XX,1qh+ were diagnosed in five children. Inversion [46,XY,inv9(p12q13)] and inversion and polymorphisms [46,XY,inv9(p12q13),13ps+] were diagnosed in two (6.0%) children, respectively.


DISCUSSION

Genetic causes of ID are highly heterogeneous, including large chromosomal abnormalities, submicroscopic copy number variants and monogenic forms due to pathogenic variants in single genes. The monogenic forms are classified based on inheritance mode to X linked, autosomal dominant and autosomal recessive ID. Close relation of the parents, double cousin or uncle-niece unions makes ID three to four times more common than in children of unrelated parents [3]. In our study, 10 (30.3%) patients who had consanguinity between the parents have the possibility of autosomal recessive ID. The high percentage of epilepsy associated with ID (36%) also supports the monogenic background.

Microarray testing is diagnostic on average in 7.8% (Class III) and G-banded karyotyping is abnormal in at least 4% (Class II and III) in patients with ID [4]. Nonetheless, microdeletion and microduplication syndromes associated with autism, developmental delay and/or multiple congenital anomalies are not detected with a karyotype [5]. In our study, we used G-banded karyotyping. Unfortunately, we could not analysed aCGH or fluorescent in situ hybridisation for subtelomeric imbalances in our patients, because of lack of laboratory facilities. This is one of the limitations in our study.

Polymorphisms are found in a rate of up to 8% in the general population. The most frequent one is inv(9). In routine cytogenetics, they are referred as heterochromatic variants or heteromorphisms [6,7]. These heteromorphisms or heterochromatic variants can include 9qh+, 9cen+, 9ph+, 9ph- and inv(9)(p11q13) [6]. Çöp et al. [8] evaluated 96 children with autism spectrum disorders for genetic testing. They found abnormalities on karyotype in 9.7% patients including inv(9)(p12q13) in a 24-month-old boy without dysmorphic features [8]. Sobreira et al. [9] described a 9-year-old girl with pseudoaminopterin syndrome, including multiple congenital malformations, who has a karyotype of 46,XX, with an inv(9)(p12q13) polymorphism. Malinverni et al. [7] reported a simple pericentric inversion of chromosome 9 [46,XX,inv(9)(p12q13)] in a patient with facial dysmorphism, language and neurodevelopmental delay and ID. Molecular cytogenetics showed an unusual, rearranged chromosome 9,der(9)(pter→p11.2::q21.11→q12::p11.2→p13.2::q12→p11.2::q21.11→qter) [6]. In our series, various polymorphisms and inv(9)(p12q13) were diagnosed in five and two children, respectively. Based on the literature data, inv(9)(p12q13) can be correlated to the patients’ phenotype; however, we think that inv(9)(p12q13) is a benign variant. We did not detect any positive result. We think that this is due to the small number of our patients, which is the second limitation of our study.


CONCLUSION

Our findings showed that the karyotype analysis was not helpful to determine etiology in children with idiopathic ID probably because of the small number of patients in our study. Although we did not detect any positive result in the present study, we still think that karyotype analysis should be performed in children with idiopathic ID as the first step test in medical centres with limited laboratory facilities.

ACKNOWLEDGMENTS

The authors would like to thank all participants who were included in this study and their families and thank all those who facilitated the accomplishment of this study.

FINANCIAL SUPPORT

This study was supported by Research Projects Directorate at Yüzüncü Yıl University (Project number: 2009-FBE-DO78).

CONFLICT OF INTEREST

There are no conflicts of interest.

ETHICS

The study was approved by Ethics Committee of Clinical Research of Erciyes University Faculty of Medicine (Date: 20.09.2011; References number: 2011/11).

REFERENCES

  1. Galasso C, Lo-Castro A, El-Malhany N, Curatolo P. “Idiopathic” mental retardation and new chromosomal abnormalities. Ital J Pediatr. 2010;36:17. https://doi.org/10.1186/1824-7288-36-17
  2. Moeschler JB. Genetic evaluation of intellectual disabilities. Semin Pediatr Neurol. 2008;15:2–9. https://doi.org/10.1016/j.spen.2008.01.002
  3. Jamra R. Genetics of autosomal recessive intellectual disability. Med Genet. 2018;30:323–7. https://doi.org/10.1007/s11825-018-0209-z
  4. Michelson DJ, Shevell MI, Sherr EH, Moeschler JB, Gropman AL, Ashwal S. Evidence report: Genetic and metabolic testing on children with global developmental delay. Report of the Quality Standards Subcommittee of the American Academy of Neurology and the Practice Committee of the Child Neurology Society. Neurology. 2011;77:1629–35. https://doi.org/10.1212/WNL.0b013e3182345896
  5. Goldenberg P. An update on common chromosome microdeletion and microduplication syndromes. Pediatr Ann. 2018;47:e198–203. https://doi.org/10.3928/19382359-20180419-01
  6. Kosyakova N, Grigorian A, Liehr T, Manvelyan M, Simonyan I, Mkrtchyan H, et al. Heteromorphic variants of chromosome 9. Mol Cytogenet. 2013;6:14. https://doi.org/10.1186/1755-8166-6-14
  7. Malinverni AC, Colovati ME, Perez AB, Caneloi TP, Oliveira HR Jr, Kosyakova N, et al. Unusual duplication in the pericentromeric region of chromosome 9 in a patient with phenotypic alterations. Cytogenet Genome Res. 2016;150:100–5. https://doi.org/10.1159/000453574
  8. Çöp E, Yurtbaşi P, Öner Ö, Münir KM. Genetic testing in children with autism spectrum disorders. Anadolu Psikiyatri Derg. 2015;16:426–32.
    https://doi.org/10.5455/apd.1414607917
  9. Sobreira N, Cernach M, Batista D, Brunoni D, Perez A. Pseudoaminopterin syndrome: clinical report with new characteristics. Am J Med Genet A. 2009;149A:2843–8. https://doi.org/10.1002/ajmg.a.33125


This Article Cited By the following articles

The odyssey of diagnosing genetic disorders in evolving health services
Sudan J Paed 2019; (): 2.

1
 
How to Cite this Article
Pubmed Style

Caksen H, Okut H, Ikbal M. Karyotype analysis in children with idiopathic intellectual disability. Sudan J Paed. 2019; 19(1): 57-59. doi:10.24911/SJP.106-1539963785


Web Style

Caksen H, Okut H, Ikbal M. Karyotype analysis in children with idiopathic intellectual disability. http://www.sudanjp.com/?mno=13463 [Access: November 12, 2019]. doi:10.24911/SJP.106-1539963785


AMA (American Medical Association) Style

Caksen H, Okut H, Ikbal M. Karyotype analysis in children with idiopathic intellectual disability. Sudan J Paed. 2019; 19(1): 57-59. doi:10.24911/SJP.106-1539963785



Vancouver/ICMJE Style

Caksen H, Okut H, Ikbal M. Karyotype analysis in children with idiopathic intellectual disability. Sudan J Paed. (2019), [cited November 12, 2019]; 19(1): 57-59. doi:10.24911/SJP.106-1539963785



Harvard Style

Caksen, H., Okut, . H. & Ikbal, . M. (2019) Karyotype analysis in children with idiopathic intellectual disability. Sudan J Paed, 19 (1), 57-59. doi:10.24911/SJP.106-1539963785



Turabian Style

Caksen, Huseyin, Hayrettin Okut, and Mevlit Ikbal. 2019. Karyotype analysis in children with idiopathic intellectual disability. Sudanese Journal of Paediatrics, 19 (1), 57-59. doi:10.24911/SJP.106-1539963785



Chicago Style

Caksen, Huseyin, Hayrettin Okut, and Mevlit Ikbal. "Karyotype analysis in children with idiopathic intellectual disability." Sudanese Journal of Paediatrics 19 (2019), 57-59. doi:10.24911/SJP.106-1539963785



MLA (The Modern Language Association) Style

Caksen, Huseyin, Hayrettin Okut, and Mevlit Ikbal. "Karyotype analysis in children with idiopathic intellectual disability." Sudanese Journal of Paediatrics 19.1 (2019), 57-59. Print. doi:10.24911/SJP.106-1539963785



APA (American Psychological Association) Style

Caksen, H., Okut, . H. & Ikbal, . M. (2019) Karyotype analysis in children with idiopathic intellectual disability. Sudanese Journal of Paediatrics, 19 (1), 57-59. doi:10.24911/SJP.106-1539963785





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