Familial aggregation in developmental topographical disorientation (DTD)

ABSTRACT

A variety of brain lesions may affect the ability to orient, resulting in what is termed “acquired topographical disorientation”. In some individuals, however, topographical disorientation is present from childhood, with no apparent brain abnormalities and otherwise intact general cognitive abilities, a condition referred to as “developmental topographical disorientation” (DTD). Individuals affected by DTD often report relatives experiencing the same lifelong orientation difficulties. Here, we sought to assess the familial aggregation of DTD by investigating its occurrence in the families of DTD probands, and in the families of control probands who did not experience topographical disorientation. We found that DTD appears to cluster in the DTD families, with tested relatives displaying the trait, whereas in the control families we did not detect any individuals with DTD. These findings provide the very first evidence for the familial clustering of DTD and motivate further work investigating the genetic factors producing this clustering.

KEYWORDS:

• Genetics
• getting lost
• heredity
• navigation
• spatial orientation

Acknowledgements

We express our most sincere gratitude to all of the families that have participated in this study. We thank Jason de Koning for his valuable input regarding statistical analyses, and Micheil Innes for his insightful comments on the manuscript.

Disclosure statement

The authors declare that they have no conflict of interest.

Additional information

Funding

This study was supported in part by the Natural Sciences and Engineering Research Council of Canada (NSERC) to G.I., and the Canadian Institutes of Health Research (CIHR) to N.T.B.H. S.F.B. was partially supported by the Alberta Children’s Hospital Research Institute (ACHRI)/CIHR Training Program. F.B. was supported by NSERC and Killam Doctoral Scholarships. K.R. was supported by an ACHRI Summer Studentship.