Early neurological signs in infants identified through neonatal screening for SMA: do they predict outcome?

Neonatal screening for SMA has allowed the identification of infants who may present with early clinical signs. Our aim was to establish whether the presence and the severity of early clinical signs have an effect on the development of motor milestones. Infants identified through newborn screening were prospectively assessed using a structured neonatal neurological examination and an additional module developed for the assessment of floppy infants. As part of the follow-up, all infants were assessed using the HINE-2 to establish developmental milestones. Only infants with at least 24 months of follow-up were included. Normal early neurological examination (n = 11) was associated with independent walking before the age of 18 months while infants with early clinical signs of SMA (n = 4) did not achieve ambulation (duration follow-up 33.2 months). Paucisymptomatic patients (n = 3) achieved ambulation, one before the age of 18 months and the other 2 between 22 and 24 months.  Conclusion: Our findings suggest that early clinical signs may contribute to predict motor milestones development. What is Known: • There is increasing evidence of heterogeneity among the SMA newborns identified via NBS. • The proposed nosology describes a clinically silent disease, an intermediate category ('paucisymptomatic') and 'symptomatic SMA'. What is New: • The presence of minimal clinical signs at birth does not prevent the possibility to achieve independent walking but this may occur with some delay. • The combination of genotype at SMN locus and clinical evaluation may better predict the possibility to achieve milestones.

Communicative development inventory in type 1 and presymptomatic infants with spinal muscular atrophy: a cohort study.

OBJECTIVE: The aim of this study was to assess early language acquisitions in treated individuals with spinal muscular atrophy (SMA) type 1 and in infants identified by newborn screening (NBS). METHODS: Parents of SMA individuals aged between 8 and 36 months were asked to fill in the MacArthur-Bates Communicative Development Inventory (MB-CDI) that assesses comprehension, gesture and expressive skills. A follow-up assessment was performed in 21 of the 36. RESULTS: The MB-CDI was completed by parents of 24 type 1 and 12 infants identified by NBS. Comprehension skills were preserved in 81% of the type 1 SMA and in 87% infants identified by NBS. Gesture abilities were <5th centile in 55% of the type 1 SMA and in none of those identified by NBS. Lexical expressions were <5th centile in more than 80% type 1 SMA and in 50% of infants identified by NBS. At follow-up, despite an increase in lexical expression skills, the scores remained below the fifth centile in 43% type 1 SMA and in 86% of infants identified by NBS. CONCLUSIONS: These results suggest that language and communication development may follow a similar pattern to that observed in motor function with the possibility to develop skills (eg, ability to say clear words) that are not usually present in untreated infants but with a level of performance that does not reach that of their typically developing peers.

Patient reported outcome measure for upper limb in Duchenne muscular dystrophy: correlation with PUL2.0.

The increasing pressure to include non ambulant Duchenne muscular dystrophy (DMD) boys in clinical trials has highlighted the need for outcome measures that could address the impact of upper limb function on activities of daily living. The aim of the present study was to establish the correlation between the recently developed Patient Reported Outcome Measure for the upper limb (PROM UL) and the observer rated functional scale Performance of Upper Limb (PUL 2.0) in a large cohort of DMD boys and young adults. As part of a larger natural history study, non ambulant DMD patients were assessed using PUL2.0 and PROM UL. One hundred and twenty-five concurrent PUL 2.0 and PROM UL evaluations from 60 non ambulant DMD boys were taken into consideration. The total PROM UL scores showed a strong correlation with both PUL 2.0 total scores and with PUL 2.0 entry item score. The strong correlation between the two tools confirms the clinical meaningfulness of the PUL2.0 and that the PROM UL can help to detect the gradient of progression of upper limb involvement.

Onasemnogene abeparvovec in spinal muscular atrophy: predictors of efficacy and safety in naïve patients with spinal muscular atrophy and following switch from other therapies.

Background: Efficacy and safety of onasemnogene abeparvovec (OA) for Spinal Muscular Atrophy infants under 7 months and <8.5 kg has been reported in clinical trials. This study examines efficacy and safety predictors in a wide age (22 days-72 months) and weight (3.2-17 kg) range, also including patients previously treated with other drugs. Methods: 46 patients were treated for 12 months between January 2020 and March 2022. Safety profile was also available for another 21 patients with at least 6 month follow-up after OA infusion. 19/67 were treatment naïve when treated with OA. Motor function was measured with the CHOP-INTEND. Findings: CHOP-INTEND changes varied among age groups. Baseline score and age at OA treatment best predicted changes. A mixed model post-hoc analysis showed that in patients treated before the age of 24 months the CHOP-INTEND changes were already significant 3 months after OA while in those treated after the age of 24 months the difference was only significant 12 months after OA. Adverse events occurred in 51/67. The risk for elevated transaminases serum levels was higher in older patients. This was also true for weight and for pre-treatment with nusinersen when analysed individually. A binomial negative regression analysis showed that only age at OA treatment had a significant effect on the risk of elevated transaminases. Interpretation: Our paper describes OA 12-month follow-up showing efficacy across various age and weight groups not targeted by clinical trials. The study identifies prognostic factors for safety and efficacy in treatment selection. Funding: None.

Type I spinal muscular atrophy patients treated with nusinersen: 4-year follow-up of motor, respiratory and bulbar function.

BACKGROUND: We report the 4-year follow-up in type I patients treated with nusinersen and the changes in motor, respiratory and bulbar function in relation to subtype, age and SMN2 copy number. METHODS: The study included SMA 1 patients with at least one assessment after 12, 24 and 48 months from the first dose of nusinersen. The assessments used were Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND) and the Hammersmith Infant Neurological Examination (HINE-II). RESULTS: Forty-eight patients, with ages ranging from 7 days to 12 years (mean 3.3 years, SD 3.6 years) were included in the study. The CHOP INTEND and HINE-II scores significantly increased between baseline and 48 months (p < 0.001). When age at starting treatment subgroups (<210 days, <2 years, 2-4 years, 5-11 years, ≥12 years) were considered, the CHOP INTEND increased significantly in patients younger than 4 years at treatment, while the HINE-2 increased significantly in patients younger than 2 years at treatment. In a mixed-model analysis, age, nutritional and respiratory status were predictive of changes on both scales while SMN2 copy number and decimal classification were not. CONCLUSIONS: Our results confirm the safety profile previously reported and support the durability of the efficacy of nusinersen at 4 years with an overall stability or mild improvement and no evidence of deterioration over a long period of time.

Comparison between EUCAST Broth Microdilution and MIC Strip Test in Defining Isavuconazole In Vitro Susceptibility against Candida and Rare Yeast Clinical Isolates.

Isavuconazole is a new broad-spectrum triazole, with significant in vitro activity against yeasts. Isavuconazole in vitro susceptibility can be evaluated through broth microdilution as a reference method. Considering difficulties in equipping such methods in a laboratory routine, a commercial MIC Strip test has been designed. This study aims to implement data about isavuconazole in vitro activity and compare EUCAST broth microdilution and MIC Strip test in defining yeast isavuconazole susceptibility. The study involved 629 isolates from positive blood cultures (January 2017-December 2021). The identified species were C. albicans (283), C. glabrata (53), C. krusei (23), C. tropicalis (68), C. parapsilosis complex (151), C. guilliermondii (12), C. famata (6), S. cerevisiae (12), C. neoformans (5), S. capitata (12), and Rhodotorula species (4). All the isolates were tested with EUCAST microdilution and MIC Strip methods. The total essential agreement between these two methods was 99.3%. As a result, we can consider that both methods are useful in testing isavuconazole susceptibility. Proposed cut-off values (P-ECOFF) were calculated using ECOFFinder software. Further studies could lead to either definitive E-COFF or clinical breakpoints, which represent the most important categorization tool of the laboratory data, allowing a better insertion of an antimicrobial drug in clinical practice.

Oral and Swallowing Abilities Tool (OrSAT) in nusinersen treated patients.

INTRODUCTION: The aim of the study was to longitudinally assess swallowing abilities in nusinersen-treated patients with type 1 spinal muscular atrophy. METHODS: Twenty infants with type 1 SMA (11 female and 9 male) treated with nusinersen between 3 weeks and 15 months of age, were assessed using the Oral and Swallowing Abilities Tool (OrSAT). The duration of the follow-up after treatment ranged between 12 months and 62 months. RESULTS: Twelve of the 20 infants had normal swallowing and there was no need for tube feeding at the time treatment started. Ten of the 12 had consistently normal swallowing with no need for tube feeding on follow-up. The other two required tube feeding but they regained the ability to eat some food by mouth.The remaining 8 infants already had tube feeding inserted at the time treatment started: 4 of them also had tracheostomy and they showed no changes on the OrSAT Scale. The other 4 who had tube feeding but no tracheostomy had partial functional improvement. CONCLUSION: Our results suggest that the degree of functional impairment at the time treatment is started can help to predict the progression of swallowing abilities. The use of a structured assessment also helped to detect partial improvements.

Neurological assessment of newborns with spinal muscular atrophy identified through neonatal screening.

The possibility to identify patients with spinal muscular atrophy through neonatal screenings has highlighted the need for clinical assessments that may systematically evaluate the possible presence of early neurological signs. The aim of this study was to use the Hammersmith Neonatal Neurological Examination (HNNE) and a module specifically designed for floppy infants to assess the possible variability of neurological findings in infants identified through neonatal screening. The infants included in this study were identified as part of a pilot study exploring neonatal screening in two Italian regions. A neurological examination was performed using the HNNE and an additional module developed for the assessment of floppy infants. Seventeen infants were identified through the screening. One patient had 1 SMN2 copy, 9 had 2 copies, 3 had 3, and 4 had more than 3 copies. Nine of the 17 infants (53%) had completely normal results on both scales, 3 had minimal signs, and the other 5 had more obvious clinical signs. The number of SMN2 copies was related to the presence of abnormal neurological signs (p = 0.036) but two SMN2 copies were associated with variable clinical signs as they were found in some infants with respectively normal examination or obvious severe early signs. CONCLUSIONS: Our results suggest that the combination of both scales increases the possibility to detect neonatal neurological signs and to define different early patterns of involvement also identifying paucisymptomatic patients. WHAT IS KNOWN: • The use of new therapeutic options in presymptomatic SMA patients leads to a dramatic reduction of the onset and severity of the diesease. • The already existing tools commonly used in Type I SMA (HINE and CHOP-intend) may not be suitable to identify minor neurological signs in the neonatal period. WHAT IS NEW: • Combining the HNNE and the floppy infant module, we were able to identify early neurological signs in SMA infants identified through newborn screening and may help to predict the individual therapeutic outcome of these patients. • Iinfants with 2 SMN2 copies identified through the screening had a more variable neonatal examination compared to those with three or more copies, in agreement with similar findings in older infants.

Nusinersen efficacy data for 24-month in type 2 and 3 spinal muscular atrophy.

The study reports real world data in type 2 and 3 SMA patients treated for at least 2 years with nusinersen. Increase in motor function was observed after 12 months and during the second year. The magnitude of change was variable across age and functional subgroup, with the largest changes observed in young patients with higher function at baseline. When compared to natural history data, the difference between study cohort and untreated patients swas significant on both Hammersmith Functional Motor Scale and Revised Upper Limb Module both at 12 months and at 24 months.

Discriminatory Weight of SNPs in Spike SARS-CoV-2 Variants: A Technically Rapid, Unambiguous, and Bioinformatically Validated Laboratory Approach.

BACKGROUND: The SARS-CoV-2 virus has assumed considerable importance during the COVID-19 pandemic. Its mutation rate is high, involving the spike (S) gene and thus there has been a rapid spread of new variants. Herein, we describe a rapid, easy, adaptable, and affordable workflow to uniquely identify all currently known variants through as few analyses. Our method only requires two conventional PCRs of the S gene and two Sanger sequencing reactions, and possibly another PCR/sequencing assay on a N gene portion to identify the B.1.160 lineage. METHODS: We selected an S gene 1312 bp portion containing a set of SNPs useful for discriminating all variants. Mathematical, statistical, and bioinformatic analyses demonstrated that our choice allowed us to identify all variants even without looking for all related mutations, as some of them are shared by different variants (e.g., N501Y is found in the Alpha, Beta, and Gamma variants) whereas others, that are more informative, are unique (e.g., A57 distinctive to the Alpha variant). RESULTS: A "weight" could be assigned to each mutation that may be present in the selected portion of the S gene. The method's robustness was confirmed by analyzing 80 SARS-CoV-2-positive samples. CONCLUSIONS: Our workflow identified the variants without the need for whole-genome sequencing and with greater reliability than with commercial kits.

Competing endogenous RNA network mediated by circ_3205 in SARS-CoV-2 infected cells.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a new member of the Betacoronaviridae family, responsible for the recent pandemic outbreak of COVID-19. To start exploring the molecular events that follow host cell infection, we queried VirusCircBase and identified a circular RNA (circRNA) predicted to be synthesized by SARS-CoV-2, circ_3205, which we used to probe: (i) a training cohort comprised of two pools of cells from three nasopharyngeal swabs of SARS-CoV-2 infected (positive) or uninfected (negative, UCs) individuals; (ii) a validation cohort made up of 12 positive and 3 negative samples. The expression of circRNAs, miRNAs and miRNA targets was assayed through real-time PCR. CircRNA-miRNA interactions were predicted by TarpMiR, Analysis of Common Targets for circular RNAs (ACT), and STarMir tools. Enrichment of the biological processes and the list of predicted miRNA targets were retrieved from DIANA miRPath v3.0. Our results showed that the predicted SARS-CoV-2 circ_3205 was expressed only in positive samples and its amount positively correlated with that of SARS-CoV-2 Spike (S) mRNA and the viral load (r values = 0.80952 and 0.84867, Spearman's correlation test, respectively). Human (hsa) miR-298 was predicted to interact with circ_3205 by all three predictive tools. KCNMB4 and PRKCE were predicted as hsa-miR-298 targets. Interestingly, the function of both is correlated with blood coagulation and immune response. KCNMB4 and PRKCE mRNAs were upregulated in positive samples as compared to UCs (6 and 8.1-fold, p values = 0.049 and 0.02, Student's t test, respectively) and their expression positively correlated with that of circ_3205 (r values = 0.6 and 0.25, Spearman's correlation test, respectively). We propose that our results convincingly suggest that circ_3205 is a circRNA synthesized by SARS-CoV-2 upon host cell infection and that it may behave as a competitive endogenous RNA (ceRNA), sponging hsa-miR-298 and contributing to the upregulation of KCNMB4 and PRKCE mRNAs.

Oral and Swallowing Abilities Tool (OrSAT) for Type 1 SMA Patients: Development of a New Module.

We describe the development of a new tool specifically designed to record oral abilities, swallowing and, more generally, feeding in young type 1 SMA patients, to be used during the first 24 months of life.The tool is composed by a checklist and a separate section summarizing the functional abilities into levels of feeding/swallowing impairment. The checklist includes 12 questions assessing aspects thought to be clinically meaningful for a type 1 SMA population and developmentally appropriate for infants during the first months of life. Each item is graded with a score of 0 or 1, depending on the child's ability to perform the activity. As some items are age-dependent, the number of items to be used, and therefore the maximum score, changes with increasing age. The levels of feeding/swallowing impairment include four levels that can be identified using easily identifiable clinical criteria.In an attempt to validate the tool in an untreated population we applied it to 24 type 1 SMA patients (age range: 2.3-24.1 months, mean: 10.8) in whom the same information collected by the new tool had been previously recorded using a less-structured format.When patients were classified in three groups according to the Dubowitz decimal classification, there was a significant difference both at baseline and at follow-up (p < 0.001). The items assessing fatigue during the nursing sessions were the most frequently impaired even in infants who did not have any other obvious clinical sign of swallowing difficulties.

Type I SMA "new natural history": long-term data in nusinersen-treated patients.

OBJECTIVE: The aim of this paper was to report the 2-year follow-up in type I patients treated with Nusinersen and to assess whether possible changes in motor function are related to the subtype, age, or SMN2 copy number. METHODS: Sixty-eight patients, with ages ranging from 0.20 to 15.92 years (mean: 3.96; standard deviation: +3.90) were enrolled in the study. All patients were assessed using the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND) and the developmental section of the Hammersmith Infant Neurological Examination (HINE-2) at the time they started treatment and 12 and 24 months after that. RESULTS: For both CHOP and HINE-2 repeated measures analysis of variance showed a significant difference (P < 0.001) between baseline and 12 months, 12 months and 24 months, and baseline and 24-month scores for the whole group. When age subgroups (<210 days, <2 years, 2-4 years, 5-11 years, 12-18 years) were considered, on the CHOP INTEND the difference was significant between baseline and 24 months in all age subgroups. On the HINE-2, the difference between baseline and 24 months was significant in all the subgroups before the age of 4 years. Age was predictive of changes on both scales (P < 0.05), whereas SMN2 copy number and decimal classification were not. INTERPRETATION: Our results suggest that some improvement of motor function can be observed even after the first year of treatment. This is more obvious in the infants treated in the first 2 years but some improvement can also be found in older children.

Sensitivity assessment of droplet digital PCR for SARS-CoV-2 detection.

Reverse transcription­quantitative polymerase chain reaction (RT­qPCR) is the gold standard method for the diagnosis of COVID­19 infection. Due to pre­analytical and technical limitations, samples with low viral load are often misdiagnosed as false­negative samples. Therefore, it is important to evaluate other strategies able to overcome the limits of RT­qPCR. Blinded swab samples from two individuals diagnosed positive and negative for COVID­19 were analyzed by droplet digital PCR (ddPCR) and RT­qPCR in order to assess the sensitivity of both methods. Intercalation chemistries and a World Health Organization (WHO)/Center for Disease Control and Prevention (CDC)­approved probe for the SARS­CoV­2 N gene were used. SYBR­Green RT­qPCR is not able to diagnose as positive samples with low viral load, while, TaqMan Probe RT­qPCR gave positive signals at very late Ct values. On the contrary, ddPCR showed higher sensitivity rate compared to RT­qPCR and both EvaGreen and probe ddPCR were able to recognize the sample with low viral load as positive even at 10­fold diluted concentration. In conclusion, ddPCR shows higher sensitivity and specificity compared to RT­qPCR for the diagnosis of COVID­19 infection in false­negative samples with low viral load. Therefore, ddPCR is strongly recommended in clinical practice for the diagnosis of COVID­19 and the follow­up of positive patients until complete remission.

Ultrasound assessment of diaphragmatic function in type 1 spinal muscular atrophy.

OBJECTIVE: To investigate ultrasound features of diaphragm motion and function in type 1 spinal muscular atrophy (SMA-1) patients. DESIGN: Prospective study. PATIENTS: The study cohort included SMA-1 children younger than 18-year-old. Control subjects included type 2 and type 3 SMA and other neuromuscular disorders younger than 18-year-old. METHODOLOGY: Diaphragm ultrasound evaluating diaphragmatic excursion, speed of diaphragmatic contraction, duration of the respiratory cycle, inspiratory/expiratory relationship, end-inspiratory and -expiratory thickness, thickening fraction, and pattern of contractility. The interrater reliability for each variable was established by calculation of Cohen's k coefficient. RESULTS: Twenty-three SMA-1 patients and 12 controls were evaluated. Diaphragm ultrasound values were within normal ranges in all study cohort patients and no difference was found with controls. There was a gradient of diaphragm function with SMA 1.9 subgroup having the best and SMA 1.1 having the worst parameters, particularly in end-inspiratory thickness and diaphragmatic excursion (P = .031 and P = .041, respectively). Seventy-four percent of SMA-1 patients had a dysmotility pattern of diaphragm contraction, mostly represented in SMA 1.9 subgroup (P = .001). This pattern was observed in 92.8% of children on noninvasive ventilation (NIV) for less than 16 hours/d of and in 20% patients with invasive ventilation or NIV for more than 16 hours/d (P = .027). The dysmotility pattern was never observed in the control group. The levels of interobserver agreement were high for "diaphragm irregularities," "inspiratory/expiratory relationship," and "diaphragm thickness," and good for the other variables. CONCLUSIONS: Ultrasound can be used to evaluate diaphragm function and contractility in SMA-1 children, providing additional information to the clinical examination and functional respiratory tests, describing a characteristic contractility pattern in these patients. Longitudinal studies are needed to understand the impact of diaphragm dysmotility and other parameters on long-term outcome in SMA-1 patients.

Transcriptional landscape of SARS-CoV-2 infection dismantles pathogenic pathways activated by the virus, proposes unique sex-specific differences and predicts tailored therapeutic strategies.

The emergence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease (COVID-19) has posed a serious threat to global health. As no specific therapeutics are yet available to control disease evolution, more in-depth understanding of the pathogenic mechanisms induced by SARS-CoV-2 will help to characterize new targets for the management of COVID-19. The present study identified a specific set of biological pathways altered in primary human lung epithelium upon SARS-CoV-2 infection, and a comparison with SARS-CoV from the 2003 pandemic was studied. The transcriptomic profiles were also exploited as possible novel therapeutic targets, and anti-signature perturbation analysis predicted potential drugs to control disease progression. Among them, Mitogen-activated protein kinase kinase (MEK), serine-threonine kinase (AKT), mammalian target of rapamycin (mTOR) and I kappa B Kinase (IKK) inhibitors emerged as candidate drugs. Finally, sex-specific differences that may underlie the higher COVID-19 mortality in men are proposed.

Nusinersen in type 1 SMA infants, children and young adults: Preliminary results on motor function.

We report preliminary data on the six month use of Nusinersen in 104 type 1 patients of age ranging from three months to 19 years, 9 months. Ten of the 104 were classified as 1.1, 58 as 1.5 and 36 as 1.9. Three patients had one SMN2 copy, 65 had two and 24 had three copies. In 12 the SMN2 copy number was not available. After six months an improvement of more than two points was found in 58 of the 104 (55.7%) on the CHOP INTEND and in 21 of the 104 (20.19%) on the Hammersmith Infant Neurological Examination (HINE). Changes more than two points were found in 26/71 patients older than two years, and in seven of the 20 older than 10 years. Changes ≥ four points were found in 20/71 older than two years, and in six of the 20 patients older than 10 years. The difference between baseline and six months on both CHOP INTEND and HINE was significant for the whole group (p < 0.001) as well as for the subgroups with two (p < 0.001), and three SMN2 copies (p < 0.001). Our preliminary results suggest that functional improvement can be observed in type 1 patients outside the range of the inclusion criteria used in the Endear study.

An observational study of functional abilities in infants, children, and adults with type 1 SMA.

OBJECTIVE: To report cross-sectional clinical findings in a large cohort of patients affected by type 1 spinal muscular atrophy. METHODS: We included 122 patients, of age ranging between 3 months and 22 years, 1 month. More than 70% (85/122) were older than 2 years and 25% (31/122) older than 10 years. Patients were classified according to the severity of phenotype and to the number of SMN2 copies. RESULTS: Patients with the more common and the most severe phenotype older than 2 years were, with few exceptions, on noninvasive ventilation and, with increasing age, more often had tracheostomy or >16-hour ventilation and a gastrostomy inserted. In contrast, 25 of the 28 patients with the mildest phenotype older than 2 years had no need for tracheostomy or other ventilatory or nutritional support. In patients older than 2 years, the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders scores were generally lower compared to those found in younger patients and showed distinct levels of functional abilities according to the severity of the phenotype. Similar findings were also observed on the Hammersmith Infant Neurological Examination. CONCLUSIONS: Our findings confirm that, after the age of 2 years, patients with type 1 spinal muscular atrophy generally survive only if they have gastrostomy and tracheostomy or noninvasive ventilation >16 hours and have low scores on the functional scales. More variability, however, can be expected in those with the mildest phenotype, who achieve head control. These data provide important baseline information at the time treatments are becoming available.

Clinical phenotypes and trajectories of disease progression in type 1 spinal muscular atrophy.

The advent of clinical trials has highlighted the need for natural history studies reporting disease progression in type 1 spinal muscular atrophy. The aim of this study was to assess functional changes using the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND) scale in a cohort of type 1 infants. Nutritional and respiratory longitudinal data were also recorded. Patients were classified according to the severity of the phenotype and age of onset. SMN2 copies were also assessed. Twenty patients were included, eight with early onset most severe phenotype, eight with the more typical type 1 phenotype and 4, who achieved some head control, with a milder phenotype. Both baseline values and trajectories of progression were different in the three subgroups (p = 0.0001). Infants with the most severe phenotype had the lowest scores (below 20) on their first assessment and had the most rapid decline. Those with the typical phenotype had scores generally between 20 and 40 and also had a fast decline. The infants with the milder phenotype had the highest scores, generally above 35, and a much slower deterioration. Infants with three SMN2 copies had an overall milder phenotype and milder progression while two SMN2 copies were found in all three subgroups.