MAJIN (membrane anchored junction protein) is a meiosis-specific protein essential for telomere attachment to the nuclear inner membrane during meiotic prophase I. 1 MAJIN functions as the membrane-anchoring subunit of the tripartite meiotic telomere complex (MTC), which also includes TERB1 and TERB2. 2 The MAJIN-TERB2-TERB1 complex mediates telomere cap exchange, whereby the shelterin complex is displaced from telomeric DNA and replaced by the MTC, creating a stable link between telomeric DNA and the inner nuclear membrane. 3 This attachment is critical for meiotic chromosome 11 and homologous pairing. 1 Mutations in MAJIN cause significant reproductive pathology. Biallelic MAJIN variants have been identified in patients with androgenetic hydatidiform moles, 4 while rare homozygous and compound heterozygous variants are associated with non-obstructive azoospermia (NOA) in men, correlating with germ cell maturation arrest. 5 Computational analyses predict that missense mutations in MAJIN can destabilize protein structure and disrupt protein-protein interactions critical for the MTC function. 6 Loss of MAJIN function abolishes telomere-nuclear envelope attachment, causing aberrant homologous pairing and disordered synapsis. 1 These findings establish MAJIN as an essential gene for successful meiosis and fertility in both sexes.