TERB1 (telomere repeat binding bouquet formation protein 1) is a meiosis-specific protein essential for male fertility that mediates telomere attachment to the inner nuclear membrane 1. TERB1 functions as a core component of the MAJIN-TERB1-TERB2 tripartite meiotic telomere complex, which orchestrates "telomere cap exchange"—the replacement of the shelterin/telosome protective cap with direct DNA binding 2. Structurally, TERB1 binds the telomeric protein TRF1 via a specialized motif to establish telomere-inner nuclear membrane connectivity, enabling homologous chromosome 16 and synapsis during meiotic prophase 13. The TERB1 MYB domain, though lacking canonical DNA-binding activity, recruits cohesin and suppresses telomere erosion during meiosis 4. Functionally, TERB1 coordinates with the SUN-KASH/LINC complex to tether telomeres to the nuclear envelope and transmit cytoskeletal forces driving chromosome 16 5. Clinically, TERB1 mutations cause non-obstructive azoospermia (NOA) through impaired spermatogenesis 67. Genetic defects in TERB1 result in germ cell maturation arrest and male infertility, with compound or homozygous variants identified in NOA patients 7. Disruption of TERB1-TRF1 interaction causes zygotene-early pachytene arrest, unpaired sex chr16, and spermatocyte apoptosis, highlighting telomere function's critical role in pseudoautosomal region pairing 3. Exome sequencing indicates that meiotic gene defects, including TERB1 variants, predict unsuccessful sperm retrieval, offering diagnostic value for treatment planning 6.