Ceroid lipofuscinosis neuronal (CLN) encompasses rare inherited neurodegenerative disorders that present in childhood with clinical features including epilepsy, psychomotor delay, progressive vision l Show more
Ceroid lipofuscinosis neuronal (CLN) encompasses rare inherited neurodegenerative disorders that present in childhood with clinical features including epilepsy, psychomotor delay, progressive vision loss, and premature death. Published experience utilizing umbilical cord blood transplant (UCBT) for these disorders is limited. This retrospective analysis includes patients with CLN (2, 3, and 5) who underwent UCBT from 2012 to 2020. All subjects (n = 8) received standard-of-care myeloablative conditioning. Four also enrolled in clinical trial NCT02254863 and received intrathecal DUOC-01 cells posttransplant. Median age at UCBT was 5.9 years. All subjects achieved neutrophil engraftment with >95% donor chimerism at a median of 28.5 days. Sinusoidal obstructive syndrome was not observed. Severe acute graft-versus-host disease occurred in 12.5%. Other complications included autoimmune hemolytic anemia (25%) and viral reactivation/infection (62.5%). No transplant-related mortality was observed. Two CLN2 patients died, 1 from progressive disease and 1 from unknown cause at days +362 and +937, respectively. With median follow-up of 8 years, overall survival at 100 days and 24 months was 100% and 88%, respectively. Three of 4 CLN3 subjects stabilized Hamburg motor and language scores. While UCBT appears safe and feasible in these patients, given the variable expression and natural history, extended follow-up and further studies are needed to elucidate the potential impact of UCBT on clinical outcomes. Show less
Patterns of amino acid conservation have served as a tool for understanding protein evolution. The same principles have also found broad application in human genomics, driven by the need to interpret Show more
Patterns of amino acid conservation have served as a tool for understanding protein evolution. The same principles have also found broad application in human genomics, driven by the need to interpret the pathogenic potential of variants in patients. Here we performed a systematic comparative genomics analysis of human disease-causing missense variants. We found that an appreciable fraction of disease-causing alleles are fixed in the genomes of other species, suggesting a role for genomic context. We developed a model of genetic interactions that predicts most of these to be simple pairwise compensations. Functional testing of this model on two known human disease genes revealed discrete cis amino acid residues that, although benign on their own, could rescue the human mutations in vivo. This approach was also applied to ab initio gene discovery to support the identification of a de novo disease driver in BTG2 that is subject to protective cis-modification in more than 50 species. Finally, on the basis of our data and models, we developed a computational tool to predict candidate residues subject to compensation. Taken together, our data highlight the importance of cis-genomic context as a contributor to protein evolution; they provide an insight into the complexity of allele effect on phenotype; and they are likely to assist methods for predicting allele pathogenicity. Show less