Table 1:

Here we summarize the described circadian phenotypes from HD models.

Phenotype	Models	Citations
Low amplitude activity rhythms	R6/2, BACHD, Q175, HD rats, HD sheep	Morton et al., 2005; Bode et al., 2009; Kudo et al., 2011; Oakeshott et al., 2011; Balci et al., 2013; Loh et al., 2013; Morton et al., 2014; Kuljis et al., 2016
Hypoactivity during active phase	BACHD, Q175,	Morton et al., 2005; Kudo et al., 2011; Loh et al., 2013; Kuljis et al., 2016;
Hyperactivity during rest phase	BACHD, Q175	Kudo et al., 2011; Loh et al., 2013; Kuljis et al., 2016;
Increase in cycle to cycle variation	BACHD, Q175	Kudo et al., 2011; Loh et al., 2013; Kuljis et al., 2016;
Disrupted rhythms in sleep, sleep fragmentation	R6/2, R6/1, Q175	Fisher et al., 2013; Kantor et al., 2013; Loh et al., 2013; Lebreton et al., 2015; Fisher et al., 2016
Low amplitude rhythms in autonomic driven rhythms in heart rate, core body temperature.	R6/1, R6/2, BACHD, Q175	Kudo et al., 2011; Kiriazis et al., 2012; Mielcarek et al., 2014; Schroeder et al., 2016; Cutler et al., 2017
Disrupted rhythms in hormones	R6/2	Dufour and McBride, 2016; Rudenko et al., 2019.
Loss of melanopsin expressing retinal ganglia cells that carry light information to the central circadian clock (SCN)	R6/2, N171-82Q	Ouk et 2016; Lin et al., 2019
Disrupted rhythms in electrical activity in the SCN	BACHD, Q175	Kuljis et al., 2016; Kuljis et al., 2018
Disrupted gene expression rhythms in central clock	R6/2	Morton et al., 2005
Disrupted gene expression rhythms outside SCN	R6/2	Morton et al., 2005; Maywood et al., 2010
Pathology in central clock	R6/2, BACHD	Fahrenkrug et al., 2007; Kuljis et al., 2016;
Circadian based treatments improving function	R6/2, BACHD, Q175	Pallier et al., 2007; Maywood et al., 2010; Cuesta et al., 2014; Skillings et al., 2014; Wang et al., 2017; Whittaker et al., 2017; Wang et al., 2018;