TEX28 (testis expressed 28) is an X-linked gene encoding a 410-amino acid protein with unknown functional homology 1. The gene is transcribed exclusively in testis tissue 1, suggesting a specialized role in male reproduction. TEX28 localizes to the endomembrane system, functioning as part of the TEX28 family of proteins involved in endoplasmic reticulum (ER) architecture. TMCC3, a TEX28 family member, resides at ER three-way junctions and facilitates proper tubular ER network formation through interactions with atlastins 2. TMCC3 knockdown decreases three-way junction numbers and expands ER sheets, indicating the TEX28 family supports critical ER structural organization 2. Regarding male infertility, TEX28 knockdown in Drosophila resulted in normal fertility, suggesting it is not essential for basic reproductive function 3. However, TEX28's testis-specific expression and potential involvement in complex genomic rearrangements affecting reproductive health warrant further investigation 4. TEX28 gains clinical relevance in MECP2 duplication syndrome, where TEX28 can be included in duplications affecting chromosome X, though its specific contribution to disease phenotype remains unclear 56. The gene's molecular function appears primarily related to ER membrane organization rather than direct fertility determination.