Heritability in spinal cord thickness â a twin study
Solstrand Dahlberg L
Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
Heritability in spinal cord thickness – a twin study
Objective: After spinal cord trauma, there is extensive degeneration of the cord, both at the site of the lesion, and above. Spinal cord thickness at the C2 level has been proposed as a biomarker of cord degeneration, but little is known about the reliability of this metric, and of underlying factors impacting individual variability in cord thickness in healthy subjects. Twin studies have reported a strong hereditary component (60 – 80%) in brain structure, but we are not aware of any studies to date investigating the heritability of the spinal cord structure. We hypothesized that spinal cord cross-sectional area at C2 would be highly hereditable.
Design/Method: Structural T1 weighted MRI data of the brain and upper cord was obtained from the Washington University-Minnesota Human Connectome Project. A test-retest sample of 34 was used for reliability estimates, and 25 monozygotic (MZ) twin pairs, 25 dizygotic (DZ) twin pairs, and 25 siblings were used for hereditability estimates. Metrics on spinal cord anterior-posterior thickness, left-right thickness and cross-sectional area was at the C2 and C3 level were extracted using a semi-automated method.
Heritability is estimated using a polygenetic AE model.
Results: Test-retest reliability of spinal cord metrics was high (ICC= 0.644). Preliminary results carried out in a subset of our sample indicate that genes account for 39,5% of variability in C2 thickness when age and gender are controlled for. This is surprisingly low in comparison to hereditability estimates of brain structure, but more firm conclusions will be reached with the full sample.
Conclusion: Gaining insight into heritability of spinal cord structure may help us understand the importance of spinal cord development and function associated with health and disease. Accurate measures of spinal cord thickness and atrophy can be prognostic for rehab success, and may prove to be an important marker for evaluating current therapies pertaining to minimizing secondary damage, and future repair and regeneration strategies.
Support: This study was supported by the Promobilia Foundation, Wings for Life and by the Department of Defense (DOD) Office of Congressionally Directed Medical Research Programs (CDMRP) SC140194 and SC140251.
You Must Be Logged In
This Reminders tab will display for your scheduled lectures 15 minutes before start time and for new messages waiting.