LMNB1 (Lamin B1): LMNB1 is a gene that encodes Lamin B1, a key component of the nuclear lamina — a fibrous layer that supports the inner nuclear membrane. Lamin B1 plays important roles in DNA replication, chromatin organization, and gene expression regulation. Changes in LMNB1 expression or mutations have been linked to developmental disorders and diseases, including laminopathies and premature aging syndromes.