In other species: chicken , goat , sheep , Japanese quail

Possibly relevant human trait(s) and/or gene(s) (MIM number): 603372 (gene)

Mendelian trait/disorder: no

Mode of inheritance: Multifactorial

Considered a defect: no

Key variant known: yes

Year key variant first reported: 2021

Species-specific name: spring and autumn spawning

Species-specific description: Chen et al. (2021): “Animals living at temperate latitudes rely on the photoperiod (day length) to adapt their behaviors … to seasonal changes. Breeding at a specific time of the year, known as seasonal reproduction, ensures that offspring are born when the environment is best suited for survival (e.g. food availability and moderate climate). Organisms that reproduce during spring with increasing photoperiod … are denoted long day (LD) breeders, and those that breed during the decreasing photoperiod in autumn …, are short day (SD) breeders. …. Atlantic herring … exhibits seasonal reproduction predominantly in spring and autumn.”

Mapping: Chen et al. (2021): “Our previous whole-genome comparisons have demonstrated that there is minute genetic differentiation between spring- and autumn-spawning herring at selectively neutral loci but striking genetic differentiation at about 30 loci (Lamichhaney et al., 2012; Martinez Barrio et al., 2016; Han et al. 2020). … The most differentiated region between spring and autumn-spawning Atlantic herring overlaps TSHR (Martinez Barrio et al., 2016; Lamichhaney et al., 2017; Pettersson et al., 2019).”

Molecular basis: Chen et al. (2021): “Two non-coding SNPs, one upstream of the promoter region and the other in intron 1, and two missense mutations, Q370H and L471M, stood out as the most strongly associated with the phenotype. … We describe, two additional sequence variants distinguishing the spring and autumn haplotypes, (i) a loss of a retrotransposon sequence upstream of TSHR and (ii) a copy number polymorphism at the C terminal end of the TSHR transcript. We show using mutagenesis and transfection experiments that the L471M substitution in the spring-allele results in enhanced constitutive cAMP signalling, and the 5.2 kb retrotransposon variant upstream of TSHR near an open chromatin region may affect TSHR expression.”

Associated gene: