Ann Lab Med.  2014 Sep;34(5):390-394. 10.3343/alm.2014.34.5.390.

A de novo Microdeletion of ANKRD11 Gene in a Korean Patient with KBG Syndrome

• Lim JH
• Seo EJ
• Kim YM
• Cho HJ
• Lee JO
• Cheon CK
• Yoo HW

• KMID: 1791956
• DOI: http://doi.org/10.3343/alm.2014.34.5.390

Abstract

KBG syndrome is a very rare genetic disorder characterized by macrodontia of upper central incisors, global developmental delay, distinctive craniofacial features, short stature, and skeletal anomalies. Ankyrin repeat domain 11 gene (ANKRD11) has recently been identified as a causal factor of this syndrome. We describe a 6-yr-old Korean boy with features of KBG syndrome. The patient had a short stature, macrodontia, dysmorphic facial features, speech and motor delay with intellectual disability, and partial seizures as indicated by the electroencephalogram, but he was neither autistic nor had autism spectrum disorders. Using high-resolution oligonucleotide array comparative genomic hybridization, we identified a heterozygous 240-kb deletion at 16q24.3 corresponding to ANKRD11. This patient provided additional evidence on the influence of ANKRD11 in KBG syndrome and suggested that deletion limited to ANKRD11 is unlikely to cause autism.

Keyword

KBG syndrome; ANKRD11; Array CGH; 16q24.3 microdeletion

MeSH Terms

Abnormalities, Multiple/diagnosis/*genetics
Asian Continental Ancestry Group/*genetics
Bone Diseases, Developmental/diagnosis/*genetics
Child
Chromosomes, Human, Pair 16
Comparative Genomic Hybridization
Electroencephalography
Facies
Gene Deletion
Heterozygote
Humans
Intellectual Disability/diagnosis/*genetics
Male
Phenotype
Repressor Proteins/*genetics
Republic of Korea
Tooth Abnormalities/diagnosis/*genetics
Repressor Proteins

Figure

• 

  Fig. 1 Array comparative genomic hybridization data showing a 240-kb deletion in the proband. The red bar is shifted to a log2 ratio of -1 in the proband and indicates the deletion overlapping ANKRD11 and SPG7 at 16q24.3.The results of both parents indicate normal copy number.

• 

  Fig. 2 Deletion boundaries in the patient reported in this study (black box covers exons 2-13 of ANKRD11 and exons 1-5 of SPG7) and previously reported cases (gray boxes). The boxes indicate the deletion size. The map is based on genome build GRCH37/hg19.

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