Study of Genetic Association With DCDC2 and Developmental Dyslexia in Hong Kong Chinese Children

Mary M.Y. Waye1, *, Lim K. Poo2, Connie S-H Ho3
1 The Nethersole School of Nursing, The Nethersole School of Nursing, The Chinese University of Hong Kong, Hong Kong
2 Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong
3 Department of Psychology, The University of Hong Kong, Hong Kong

Article Metrics

CrossRef Citations:
Total Statistics:

Full-Text HTML Views: 925
Abstract HTML Views: 486
PDF Downloads: 235
ePub Downloads: 169
Total Views/Downloads: 1815
Unique Statistics:

Full-Text HTML Views: 590
Abstract HTML Views: 261
PDF Downloads: 198
ePub Downloads: 143
Total Views/Downloads: 1192

Creative Commons License
© 2017 Waye et al.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

* Address correspondence to this author at the Department Rm 726, 7th floor, Esther Lee Bldg, The Nethersole School of Nursing, The Chinese University of Hong Kong, Shatin, N.T. Hong Kong, Tel: (852) 39439302; Email:



Doublecortin domain-containing 2 (DCDC2) is a doublecortin domain-containing gene family member and the doublecortin domain has been demonstrated to bind to tubulin and enhance microtubule polymerization. It has been associated with developmental dyslexia and this protein family member is thought to function in neuronal migration where it may affect the signaling of primary cilia.


The objective of the study is to find out if there is any association of genetic variants of DCDC2 with developmental dyslexia in Chinese children from Hong Kong.


The dyslexic children were diagnosed as developmental dyslexia (DD) using the Hong Kong Test of Specific Learning Difficulties in Reading and Writing (HKT-SpLD) by the Department of Health, Hong Kong. Saliva specimens were collected and their genotypes of DCDC2 were studied by DNA sequencing or TaqMan Real Time PCR Assays.


The most significant marker is rs6940827 which is associated with DD with nominal p-value (0.011). However, this marker did not remain significant after multiple testing corrections and the adjusted p-value from permutation test was 0.1329. Using sliding window haplotype analysis, several haplotypes were found to be nominally associated with DD. The smallest nominal p values was 0.0036 (rs2996452-rs1318700, C-A). However, none of the p values could withstand the multiple testing corrections.


Despite early findings that DCDC2 is a strong candidate for developmental dyslexia and that some of the genetic variants have been linked to brain structure and functions, our findings showed that DCDC2 is not strongly associated with dyslexia.

Keywords: DCDC2, Developmental dyslexia, Genetic association, Sliding window haplotype analysis, Genetic variants, Chinese.