Freezing behavior is used as a measure of a rodent’s ability to learn during fear conditioning. However, it is possible that the expression of other behaviors may compete with freezing, particularly in rodent populations that have not been thoroughly studied in this context. Rearing and grooming are complex behaviors that are frequently exhibited by mice during fear conditioning. Both behaviors have been shown to be stress-sensitive, and the expression of these behaviors is dependent upon strain background. To better understand how genetic background impacts behavioral responses during fear conditioning, we examined freezing, rearing, and grooming frequencies prior to fear conditioning training and across different stages of fear conditioning testing in male mice from eight inbred mouse strains (C57BL/6J, DBA/2J, FVB/NJ, SWR/J, BTBR T + ltpr3Tf/J, SM/J, LP/J, 129S1/SvlmJ) that exhibited diverse freezing responses. We found that genetic background determined rearing and grooming expression throughout fear conditioning, and their patterns of expression across stages of fear conditioning were strain dependent. Using publicly available SNP data, we found that polymorphisms in Dab1, a gene that is implicated in both grooming and learning phenotypes, separated the strains with high contextual grooming from the others using a hierarchical clustering analysis. This suggested a potential genetic mechanism for the observed behavioral differences. These findings demonstrate that genetic background determines behavioral responses during fear conditioning and suggest that shared genetic substrates underlie fear conditioning behaviors.

冻结行为被用来衡量啮齿动物在恐惧条件反射期间的学习能力。然而，其他行为的表达可能会与冻结竞争，特别是在尚未在此背景下彻底研究的啮齿动物种群中。饲养和梳理毛发是小鼠在恐惧条件反射期间经常表现出的复杂行为。这两种行为都被证明是压力敏感的，并且这些行为的表达取决于应变背景。为了更好地了解遗传背景如何影响恐惧条件反射期间的行为反应，我们检查了恐惧条件反射训练之前的冻结、饲养和梳理频率，以及来自八种近交小鼠品系（C57BL/6J，DBA/ 2J、FVB/NJ、SWR/J、BTBR T + ltpr3Tf/J、SM/J、LP/J、129S1/SvlmJ）表现出不同的冷冻反应。我们发现遗传背景决定了整个恐惧条件反射的饲养和梳理表达，并且它们在恐惧条件反射阶段的表达模式依赖于应变。使用公开可用的 SNP 数据，我们发现多态性在Dab1是一种与修饰和学习表型有关的基因，它使用层次聚类分析将具有高度上下文修饰的菌株与其他菌株分开。这表明了观察到的行为差异的潜在遗传机制。这些发现表明，遗传背景决定了恐惧条件反射期间的行为反应，并表明共享的遗传底物是恐惧条件反射行为的基础。