Usefulness of fragile X checklist and CGG distribution in specialized institutions in Kinshasa, DR Congo
Screening for fragile X syndrome (FXS) is essential in children with developmental delay or intellectual disability (ID). In addition, using clinical screening checklists remains of high interest in resource-limited settings. We aimed to gain insight into the prevalence of FXS and the distribution of CGG alleles and to evaluate the usefulness of three checklists in specialized institutions in Kinshasa, DR Congo. We recruited 80 males and 25 females from six specialized institutions in Kinshasa and administered a questionnaire comprising items from the following FXS checklists: Hagerman, Maes, and Guruju. FMR1 CGG repeats were assessed for every patient. About 37% of patients were referable for FX testing based on Hagerman’s checklist, 35% for Maes’, and 43.80% for Guruju’s, but none of them was molecularly confirmed to have FXS. Thus, specificities were 62.86, 64.76, and 56.5%, respectively, for Hagerman, Maes, and Guruju, respectively. The mean CGG allele size was 28.55 ± 2.83 (ranges, 17–48). The 29 CGG was the most frequent allele (24.61%). Thus, existing checklists should not be automatically applied to Congolese patients without adjustments. The distribution of CGG repeats and the number of CGG alleles are similar to other African studies.
KeywordsFragile X syndrome Checklist Behavioral manifestation Dysmorphism Democratic Republic of Congo
The authors are grateful to the laboratory of Prof Gert Matthijs; to Bijou Myndyo, Ervie-Winner, Eben and Etsa-Edi Lumaka, Cathy Nkunku, and Dr. Gerrye Mubungu for their strong contribution and support to this work.
A.L. acknowledges the contribution of the Research Foundation - Flanders (FWO) travel grants for research abroad (ref: V405213N and K210115) to this research.
Compliance with ethical standards
All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000(5). Informed consent was obtained from all patients for being included in the study.
Our research protocol was approved under the number ESP/CE/008/2015 by the National Ethical Committee of the Public Health School of the University of Kinshasa, Kinshasa, DR Congo.
Conflict of interest
The authors declare that they have no conflict of interest.
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