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Neuropediatrics 2020; 51(01): 076-082
DOI: 10.1055/s-0039-1698421
Short Communication
Georg Thieme Verlag KG Stuttgart · New York

Further Insights into Developmental Brain Malformations and Leukoencephalopathy Associated with 6p25.3 Deletion

Maha Eid
1   Human Cytogenetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
,
Ola Eid
1   Human Cytogenetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
,
Ibrahim Hegazy
2   Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
,
Marian Girgis
3   Pediatric Department, Faculty of Medicine, Cairo University, Cairo, Egypt
,
Amal Mohamed
1   Human Cytogenetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
,
Ghada M.H. Abdel-Salam 
2   Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
› Author Affiliations
Further Information

Publication History

11 May 2019

18 August 2019

Publication Date:
21 October 2019 (online)

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Abstract

We report a new patient who presented with dysmorphic features and congenital heart disease. In addition, her brain magnetic resonance imaging revealed leukoencephalopathy, cavum septum pellucidum, perisylvian polymicrogyria, and focal occipital pachygyria. Her regular karyotype showed 46,XX add 6 (p25) due to malsegregation of a maternal balanced translocation 46,XX,t(6;7)(p25;q33) while the array-comparative genomic hybridization identified a 3.307 Mb heterozygous deletion at 6p25.3-p25.2 and 23.95 Mb duplication at 7q33-q36.3. A previous patient with the same developmental brain malformations and leukoencephalopathy with 6p25 deletion including TUBB2A and TUBB2B genes had been reported. Thus, confirming that these specific developmental brain malformations are due to TUBB2A and TUBB2B haploinsufficiency. Our report is the first to present the developmental brain malformations associated with whole gene deletions of the two tubulin genes and provide further insights into the etiology of developmental brain malformations and white matter abnormalities associated with 6p25 deletions.

Keywords

6p25 deletion - 7q33-q36.3 duplication - leukoencephalopathy - pachygyria - polymicrogyria - atrial septal defect - TUBB2A - TUBB2B
 

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