Fertilization time and oocyte spindle integrity: implication for embryo ploidy.

Although the number of tobacco users has declined steadily over the past two decades, an estimated 1.2 billion people worldwide still used tobacco in 2024. China ranks as the world’s foremost producer and consumer of tobacco products, with approximately 25.6% of adults, aged ≥18 years, smoking. Nicotine dependence (ND) is widely recognized as a key factor in persistent smoking. Understanding the neurobiological mechanisms underlying ND is crucial for developing effective smoking cessation interventions. Metabotropic glutamate receptor 7 (, also known as 7) is a member of the group III metabotropic glutamate receptor family. Expression of is widespread throughout the central nervous system (CNS), e.g. the prefrontal cortex, hippocampus, and amygdala. is thought to be essential for a wide range of CNS functions, including memory, learning, cognition, and emotion. Notably, was found to be involved in multiple neurodevelopmental and neuropsychiatric disorders, including but not limited to autism, bipolar disorder, and schizophrenia. For example, in valproic acid-treated C57BL/6J mice, overexpression of in the prefrontal cortex could ameliorate autism spectrum disorder behaviors. It has been reported that down-regulation of expression enhanced ethanol consumption and conditioned place preference in male rats. Activation of inhibits cocaine-seeking, reducing drug self-administration in rats. Additionally, was linked to vulnerabilities to ND in a 520000 single-nucleotide polymorphisms (SNPs)-based genome-wide association study (GWAS). Another GWAS further supported the involvement of in smoking initiation and current smoking, in which four SNPs, i.e. rs162773, rs13070476, rs779714, and rs1868616, were found to be associated. In a COPDGene cohort, a polymorphic CNV segment from the intergenic region of showed a significant association with pack-years (smoked cigarette packs per day times the years of smoking). These findings highlight the intricate role of in addiction neurobiology.