LMAN2L encodes a lectin mannose-binding protein functioning as an endoplasmic reticulum (ER) cargo receptor involved in glycoprotein transport 1. The protein localizes to the ER-Golgi intermediate compartment and regulates export of glycoproteins from the ER 1. LMAN2L is targeted by human cytomegalovirus pUS2 protein through TRC8-dependent ER-associated degradation, affecting cell surface trafficking of proteins like integrin alpha-6 2. Pathogenic variants in LMAN2L cause autosomal recessive intellectual disability with seizures (autosomal recessive mental retardation-52) 13. Compound heterozygous mutations have been linked to early childhood refractory epilepsy with seizure onset at 2 months 3. Additionally, LMAN2L variants associate with bipolar disorder and schizophrenia 4, and reduced plasma LMAN2L levels correlate with increased bipolar disorder risk 5. LMAN2L is also causally associated with sarcopenia 6 and identified as a risk factor protein in IgA nephropathy pathogenesis 7. Notably, LMAN2L expression is markedly decreased in early-stage COPD with emphysema 8. These diverse disease associations suggest LMAN2L plays critical roles in protein trafficking and neuropsychiatric/systemic disease pathways.