Novel IGFALS mutations with predicted pathogenetic effects by the analysis of AlphaFold structure

PURPOSE

According to the American College of Medical Genetics (ACMG) classification, variants of uncertain significance (VUS) are gene variations whose impact on the disease risk is not yet known. VUS, therefore, represent an unmet need for genetic counselling. Aim of the study is the use the AlphaFold artificial intelligence algorithm to predict the impact of novel mutations of the IGFALS gene, detected in a subject with short stature and initially classified as VUS according to the ACMG classification.

METHODS

A short-stature girl and her parents have been investigated. IGFALS mutations have been detected through clinical exome and confirmed by Sanger sequencing. The potential presence of co-occurring gene alterations was investigated in the proband by whole exome and CGH array. Structure of the ALS protein (encoded by the IGFALS gene) was evaluated through the AlphaFold artificial intelligence algorithm.

RESULTS

Two IGFALS variants were found in the proband: c.1349T > C (p.Leu450Pro) and c.1363_1365delCTC (p.Leu455del), both classified as VUS, according to ACMG. Parents' analysis highlighted the in trans position of the two variants. AlphaFold showed that the mutated positions were found the concave side a horseshoe structure of the ALS protein, likely interfering with protein-protein interactions. According to a loss of function (LoF) effect of the two variants, reduced levels of the IGF1 and IGFBP-3 proteins, as well as a growth hormone (GH) excess were detected in the proband's serum.

CONCLUSIONS

By using the AlphaFold structure we were able to predict two IGFALS gene mutations initially classified as VUS, as potentially pathogenetic. Our proof-of-concept showed a potential application of AlphaFold as tool to a better inform VUS interpretation of genetic tests.

Management of Childhood-onset Craniopharyngioma in Italy: A Multicenter, 7-Year Follow-up Study of 145 Patients

CONTEXT

Nationwide data on children diagnosed with craniopharyngioma (CP) are not available in Italy.

OBJECTIVE

This work aimed to identify patients' characteristics, type of surgical approach, complications and recurrences, number of pituitary deficits, and number of patients starting growth hormone (GH) treatment.

METHODS

A retrospective multicenter collection took place of 145 patients aged 0 to 18 years who underwent surgery for CP between 2000 and 2018, and followed up in 17 Italian centers of pediatric endocrinology.

RESULTS

Age at diagnosis was 8.4 ± 4.1 years. Duration of symptoms was 10.8 ± 12.5 months and headache was most frequent (54%), followed by impaired growth (48%) and visual disturbances (44%). Most lesions were suprasellar (85%), and histology was adamantinomatous in all cases but two. Surgical approach was transcranial (TC) in 67.5% of cases and transsphenoidal (TS) in 31.%. The TC approach was prevalent in all age groups. Postsurgery complications occurred in 53% of cases, with water-electrolyte disturbances most frequent. Radiotherapy was used in 39% of cases. All patients but one presented with at least one hormone pituitary deficiency, with thyrotropin deficiency most frequent (98.3%), followed by adrenocorticotropin (96.8%), arginine vasopressin (91.1%), and GH (77.4%). Body mass index (BMI) significantly increased over time. A hypothalamic disturbance was present in 55% of cases. GH therapy was started during follow-up in 112 patients at a mean age of 10.6 years, and 54 developed a recurrence or regrowth of the residual lesion.

CONCLUSION

CP is often diagnosed late in Italy, with TC more frequent than the TS surgical approach. Postsurgery complications were not rare, and hypopituitarism developed almost in all cases. BMI shows a tendency to increase overtime.

The Interplay among BMI z-Score, Peer Victmization, and Self-Concept in Outpatient Children and Adolescents with Overweight or Obesity

BACKGROUND

Research has provided evidence that obesity is associated with peer victimization and low levels of self-concept. No study has examined the relationship between BMI z-score, self-concept in multiple domains, and peer victimization.

METHODS

The aim of the research was to investigate the interplay between BMI z-score, self-concept in multiple domains (physical, athletic, social), and peer victimization, testing direct, mediated, and moderated associations. Eighty hundred fifteen outpatient children and adolescents were consecutively recruited in 14 hospitals distributed over the Italian country. The sample consisted of 419 males and 396 females; mean age 10.91 ± 1.97 years (range 6-14 years) and mean BMI z-score 1.85 ± 0.74 (range -0.97 ± 3.27). Peer victimization and self-concept were assessed with a revised Olweus Bully/Victim Questionnaire and with the Self-Perception Profile for Children. A structural equation model approach was used to determine the associations among variables, testing two competing models.

RESULTS

In both models, path analysis revealed that BMI z-score was directly associated with peer victimization and self-concept in multiple domains. In the first model, peer victimization mediated the relationship between BMI-score and self-concept, whereas in the alternative model, self-concept mediated the relationship between BMI z-score and peer victimization. Interaction analyses revealed that social competence moderated the relationship between BMI z-score and peer victimization and that peer victimization moderated the relationship between BMI z-score and physical appearance.

CONCLUSIONS

Higher levels of BMI z-score are a risk factor for peer victimization and poor self-concept. When high levels of BMI z-score are associated with a negative self-concept, the risk of victimization increases. Preventive and supportive interventions are needed to avoid negative consequences on quality of life in children and adolescents with obesity.

Bullying and Victimization in Overweight and Obese Outpatient Children and Adolescents: An Italian Multicentric Study

OBJECTIVE

Being overweight or obese is one of the most common reasons that children and adolescents are teased at school. We carried out a study in order to investigate: i) the relation between weight status and school bullying and ii) the relation between weight status categories and types of victimization and bullying in an outpatient sample of Italian children and adolescents with different degrees of overweight from minimal overweight up to severe obesity.

PARTICIPANTS/METHODS

Nine-hundred-forty-seven outpatient children and adolescents (age range 6.0-14.0 years) were recruited in 14 hospitals distributed over the country of Italy. The participants were classified as normal-weight (N = 129), overweight (N = 126), moderately obese (N = 568), and severely obese (N = 124). The nature and extent of verbal, physical and relational bullying and victimization were assessed with an adapted version of the revised Olweus bully-victim questionnaire. Each participant was coded as bully, victim, bully-victim, or not involved.

RESULTS

Normal-weight and overweight participants were less involved in bullying than obese participants; severely obese males were more involved in the double role of bully and victim. Severely obese children and adolescents suffered not only from verbal victimization but also from physical victimization and exclusion from group activities. Weight status categories were not directly related to bullying behaviour; however severely obese males perpetrated more bullying behaviour compared to severely obese females.

CONCLUSIONS

Obesity and bullying among children and adolescents are of ongoing concern worldwide and may be closely related. Common strategies of intervention are needed to cope with these two social health challenges.

Genomics in pediatric endocrinology-genetic disorders and new techniques

In the last few years, there have been remarkable advances in the development of new and more sophisticated genetic techniques. These have allowed a better understanding of the molecular mechanisms of genetically determined pediatric endocrine disorders and are paving the way for a radical change in diagnosis and treatment. This article introduces some of these concepts and some of the genetic techniques being used.

Genomics in pediatric endocrinology--genetic disorders and new techniques

In the last few years, there have been remarkable advances in the development of new and more sophisticated genetic techniques. These have allowed a better understanding of the molecular mechanisms of genetically determined pediatric endocrine disorders and are paving the way for a radical change in diagnosis and treatment. This article introduces some of these concepts and some of the genetic techniques being used.

A comparison study of the prevalence of overweight and obese Italian preschool children using different reference standards

INTRODUCTION

The number of overweight children is constantly increasing in both developed and underdeveloped countries. Most epidemiological surveys consider school age children with little attention being given to preschool age children. This study was undertaken to define the prevalence of being overweight or obese in a population of children 3-6 years of age, living in North-East Italy. We also identified differences when comparing body mass index (BMI) data against three different national and international standards.

SUBJECTS AND METHODS

The study involved 258 children (124 males and 134 females) with an average age of 4.8 years. Weight and height were obtained for each child and BMI was calculated according to the formula weight (kg)/height (m)(2). The prevalence of overweight and obese subjects was then determined using the growth curves of the Centers for Disease Control and Prevention (CDC), the growth curves of the International Obesity Task Force (IOTF) and the curves published in 2003 by Luciano et al.

RESULTS

All three methods gave similar, but not identical, estimates of the prevalence of overweight in both boys and girls. However, when determining the prevalence of obesity, the use of the CDC curves led to a significantly higher prevalence of obesity in both males and females when compared to the growth charts of the IOTF and Luciano et al.

BACKGROUND

The use of the CDC growth curves leads to an increase in the prevalence of obesity when evaluating children under 5 years of age. The lower cut-off values inherent in the CDC charts, in contrast to the ones proposed by the IOTF, allow for earlier identification of a larger number of subjects with weight problems and therefore provide the potential for earlier intervention.