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Background: Spinal muscular atrophy (SMA) is a genetic disease characterized by loss of motor neurons in the spinal cord and lower brainstem. The term “SMA” usually refers to the most common form, 5q-SMA, which is caused by biallelic mutations in SMN1 (located on chromosome 5q13). However, long before the discovery of SMN1, it was known that other forms of SMA existed. Therefore, SMA is currently divided into two groups: 5q-SMA and non-5q-SMA. This is a simple and practical classification, and therapeutic drugs have only been developed for 5q-SMA (nusinersen, onasemnogene abeparvovec, risdiplam) and not for non-5q-SMA disease. Methods: We conducted a non-systematic critical review to identify the characteristics of each SMA disease. Results: Many of the non-5q-SMA diseases have similar symptoms, making DNA analysis of patients essential for accurate diagnosis. Currently, genetic analysis technology using next-generation sequencers is rapidly advancing, opening up the possibility of elucidating the pathology and treating non-5q-SMA. Conclusion: Based on accurate diagnosis and a deeper understanding of the pathology of each disease, treatments for non-5q-SMA diseases may be developed in the near future. Full article

Abundant genetic variation among the geographical provenances of Juglans mandshurica. The biomass and allometry of 3-year-old J. mandshurica seedlings were studied among 21 Chinese provenances to understand the variations in biomass allocation in depth. Standardized major axis (SMA) regression analysis was used to analyze the allometry relationship between the organs and whole plants or between the organs of plants from different provenances. Pearson correlation analysis determined the correlation of various biomass traits and the geographical and climatic factors of provenances. Significant variations (p < 0.001) in seedling biomass and its distribution were observed among the different provenances. The root, stem, leaf, aboveground, and total biomasses of Hongshi, Ji’an, Fangzheng, and Kuandian provenances were the highest, but their root allocation and root–shoot ratios were all lower. This phenomenon is just the opposite in the Lushuihe provenance. An extremely marked positive correlation (p < 0.001) was detected among the root, stem, leaf, aboveground, and total biomasses, but there were significant negative correlations (p < 0.001) among the biomass allocation ratios (except between root allocation and root–shoot ratios). The organs, aboveground, and total biomasses were mainly positively affected by annual mean precipitation except for leaf biomass. The allometric growth relationship between the organs or between the organs (except roots) and whole plants of J. mandshurica changed remarkably among the provenances (p < 0.05). The organ–biomass allocation in J. mandshurica seedlings conspicuously varied among the different provenances, which was mainly caused by the genetic variations in the seeds. This study provided the basis for the selection of optimal provenances for J. mandshurica seedlings. Full article