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BackgroundCeliac disease (CD) has a strong genetic component mainly due to HLA DQ2/DQ8 encoding genes. However, a minority of CD patients are DQ2/DQ8-negative. To address this issue, we retrospectively characterized HLA haplotypes in 5,535 subjects at risk of CD (either relatives of CD patients or subjects with CD-like symptoms) referred to our center during a 10-year period.MethodsWe identified loci DQA1/DQB1/DRB1 by sequence-specific oligonucleotide-PCR and sequence-specific primer-PCR; anti-transglutaminase IgA/IgG and anti-endomysium IgA by ELISA and indirect immunofluorescence, respectively.ResultsWe diagnosed CD in 666/5,535 individuals, 4.2% of whom were DQ2/DQ8-negative. Interestingly, DQ7 was one of the most abundant haplotypes in all CD patients and significantly more frequent in DQ2/DQ8-negative (38%) than in DQ2/DQ8-positive CD patients (24%) (pConclusionOur data lend support to the concept that DQ7 represents an additive or independent CD risk haplotype with respect to DQ2/DQ8 haplotypes but this finding should be verified in other large CD populations.

Type 2 Maturity Onset Diabetes of the Young (MODY2) is a monogenic autosomal disease characterized by a primary defect in insulin secretion and hyperglycemia. It results from GCK gene mutations that impair enzyme activity. Between 2006 and 2010, we investigated GCK mutations in 66 diabetic children from southern Italy with suspected MODY2. Denaturing High Performance Liquid Chromatography (DHPLC) and sequence analysis revealed 19 GCK mutations in 28 children, six of which were novel: p.Glu40Asp, p.Val154Leu, p.Arg447Glyfs, p.Lys458_Cys461del, p.Glu395_Arg397del and c.580-2A>T. We evaluated the effect of these 19 mutations using bioinformatic tools such as Polymorphism Phenotyping (Polyphen), Sorting Intolerant From Tolerant (SIFT) and in silico modelling. We also conducted a functional study to evaluate the pathogenic significance of seven mutations that are among the most severe mutations found in our population, and have never been characterized: p.Glu70Asp, p.His137Asp, p.Phe150Tyr, p.Val154Leu, p.Gly162Asp, p.Arg303Trp and p.Arg392Ser. These seven mutations, by altering one or more kinetic parameters, reduced enzyme catalytic activity by >40%. All mutations except p.Glu70Asp displayed thermal-instability, indeed >50% of enzyme activity was lost at 50°C/30 min. Thus, these seven mutations play a pathogenic role in MODY2 insurgence. In conclusion, this report revealed six novel GCK mutations and sheds some light on the structure-function relationship of human GCK mutations and MODY2.

Celiac Disease (CD) is a polygenic trait, and HLA genes explain less than half of the genetic variation. Through large GWAs more than 40 associated non-HLA genes were identified, but they give a small contribution to the heritability of the disease. The aim of this study is to improve the estimate of the CD risk in siblings, by adding to HLA a small set of non-HLA genes. One-hundred fifty-seven Italian families with a confirmed CD case and at least one other sib and both parents were recruited. Among 249 sibs, 29 developed CD in a 6 year follow-up period. All individuals were typed for HLA and 10 SNPs in non-HLA genes: CCR1/CCR3 (rs6441961), IL12A/SCHIP1 and IL12A (rs17810546 and rs9811792), TAGAP (rs1738074), RGS1 (rs2816316), LPP (rs1464510), OLIG3 (rs2327832), REL (rs842647), IL2/IL21 (rs6822844), SH2B3 (rs3184504). Three associated SNPs (in LPP, REL, and RGS1 genes) were identified through the Transmission Disequilibrium Test and a Bayesian approach was used to assign a score (BS) to each detected HLA+SNPs genotype combination. We then classified CD sibs as at low or at high risk if their BS was respectively < or ≥ median BS value within each HLA risk group. A larger number (72%) of CD sibs showed a BS ≥ the median value and had a more than two fold higher OR than CD sibs with a BS value < the median (O.R = 2.53, p = 0.047). Our HLA+SNPs genotype classification, showed both a higher predictive negative value (95% vs 91%) and diagnostic sensitivity (79% vs 45%) than the HLA only. In conclusion, the estimate of the CD risk by HLA+SNPs approach, even if not applicable to prevention, could be a precious tool to improve the prediction of the disease in a cohort of first degree relatives, particularly in the low HLA risk groups.

We surveyed a convenience sample of 362 Italian university physics students, asking them to retrospectively assess their experience of emergency remote instruction due to the COVID-19 outbreak. We looked at their psychological well being, motivation for physics, academic orientation, attitude towards physics and physicists, and tried to link these factors to their overall perception of the online instruction. Our results show a general appreciation for the organization and effectiveness of online courses. However, online teaching negatively impacted on engagement and interaction between peers and with the instructors. Only 22% of students in our sample complained of the psychological distress due to remote instruction. Nonetheless, we found a significant decrease in motivational dimensions, such as interest and recognition. Emergency remote instruction also challenged the students’ self-regulation, self-efficacy, and engagement. Finally, the uncertainty about the future resulted in a more pessimistic attitude towards physics, academic performance, and job perspectives.

We describe how young students situate themselves with respect to astronomy through an identity framework that features four dimensions: interest, utility value, confidence, and conceptual knowledge. Overall, about 900 Italian students, from 5th to 9th grade (9–14 years old), were involved in the study. We tested our model using confirmatory factor analysis and structural equation modeling. Differences between girls and boys and across school levels were also investigated. Results show that interest has both a direct and an indirect effect on astronomy identity. The indirect effect of interest on identity is mediated by utility value. Moreover, confidence mediates the effect of interest on conceptual knowledge. Concerning differences between girls and boys, we found that the effect of interest on identity is greater for girls than for boys and that the utility value mediates the effect of interest on identity for boys but not for girls. Finally, our findings show also that the students’ interest in astronomy and confidence in their performance decrease with age, with a potential negative impact on conceptual knowledge and future career choice in astronomy. The astronomy identity framework can be employed to examine the role of affective variables on performance and persistence in astronomy and to improve the design of teaching-learning activities that can potentially stimulate a lasting interest in astronomy.

We present the development and validation of a construct map addressing introductory quantum mechanics topics at the high school level, as a subset of a larger learning progression on quantum mechanics. Topics include energy quantization, photon absorption and emission, the Heisenberg uncertainty principle, atom stability, orbitals, wave function, and electronic properties of materials. To validate the hypothesized construct map, we designed a multiple-choice questionnaire and a 14-h teaching-learning sequence (TLS) designed in strict relation with the levels of the construct map. Twenty-three classes of Italian students (ages 17–18, N=408) were involved in the study: about half (N=200) were exposed to the TLS, while N=208 students received a typical textbook instruction on the same topics targeted by the construct map. Data were analyzed using a 1D Rasch model. Results show that the proposed construct map consistently describes the increasing abilities of students when exposed to instruction. In particular, when exposed to the TLS activities, students more likely move towards the upper levels of the construct map. Findings have implications for instruction designed to support students’ learning in quantum mechanics at the high school level.

Students’ ability to assess their own knowledge is an important skill in science education. However, students often overestimate their actual performances. In such cases, overconfidence bias arises. Previous studies in physics education have shown that overconfidence bias concerns mainly content areas, such as Newtonian mechanics, where misconceptions are strongly held by students. However, how the received instruction and the levels of understanding of a given topic influence overconfidence bias is yet to be proved. In this paper, we address this issue choosing as content area introductory quantum mechanics (QM). Overall, 408 high school students were involved in the study and randomly assigned to two experimental groups. One group received a textbook-based instruction about introductory QM, whereas the other one received instruction on the same topics through an innovative guided inquiry teaching-learning sequence (TLS), which included also potential pedagogical countermeasures for overconfidence bias. Students of both experimental groups completed a multiple-choice questionnaire and indicated for each item the degree of their confidence in the given answer using a 5-point Likert scale. The overconfidence bias was quantitatively defined and evaluated at person level using a 1D Rasch model. Progress in knowledge about the targeted topics was modeled according to a construct map validated in a previous paper. Results show that, for the whole sample, the overconfidence bias decreased as students progressed along the levels of the construct map. However, findings indicate that students of the TLS group achieved a significantly higher accuracy and a better confidence calibration, while the textbook group exhibited a lower performance and a significantly greater overconfidence bias. Implications for research into overconfidence bias in physics education are briefly discussed.

We present the design, statistical analysis, and validation of a questionnaire to assess students’ knowledge about basic aspects of quantum mechanics (QM). The QM evaluation (QME) is a true-false and multiple-choice mixed questionnaire that features 10 two-tier items spanning three relevant themes in quantum mechanics: wave behavior of matter, measurement, and atoms and electrons behavior. Its validity was assessed through a pilot administration to students and interviews with course instructors. We checked its internal consistency using both classic test theory and Rasch analysis to account for the different difficulty of each tier and for different scoring methods of the items. The questionnaire was administered to about 450 undergraduate physics students and high school physics teachers. Data show that it is a reliable instrument and all items have a good discriminatory power. Since the test does not require an advanced mathematical knowledge, it ideally lends itself to probe students’ knowledge about quantum mechanics in a variety of university courses, from the introductory ones to those more formal and mathematically oriented.

[This paper is part of the Focused Collection on Astronomy Education Research.] Several decades of research have contributed to our understanding of students’ reasoning about astronomical phenomena. Some authors have pointed out the difficulty in reading and interpreting images used in school textbooks as factors that may justify the persistence of misconceptions. However, only a few studies have investigated to what extent usual textbook images influence students’ understanding of such phenomena. This study examines this issue, exploring 13–14 year old students’ explanations, drawings, and conceptions about three familiar phenomena: change of seasons, Moon phases, and solar or lunar eclipses. The research questions that guided the study were (RQ1) how are students’ explanations and visual representations about familiar astronomical phenomena affected by different image-support conditions? (RQ2) How are students’ conceptions about familiar astronomical phenomena affected by different image-support conditions? (RQ3) Which features of the used images most affected the students’ visual representations and explanations of familiar astronomical phenomena? To answer our research questions, we designed three instructional contexts under increasing support conditions: textbook images and text, teaching booklets with specially designed images and text, only text. To analyze students’ drawings, we used exploratory factor analysis to deconstruct drawings into their most salient elements. To analyze students’ explanations, we adopted a constant comparison method identifying different levels of increasing knowledge. To investigate students’ conceptions, we used a mixed multiple-choice and true false baseline questionnaire. For RQ1, results show that the specially designed images condition was effective in helping students producing informed drawings in comparison to text-only condition for all phenomena, and more effective than textbook images condition when one considers seasonal change drawings. Concerning RQ2, the specially designed images condition was the most effective for all phenomena. Concerning RQ3, prevalent elements of astronomy images that affected students’ explanations and visual representations were Earth’s elliptical orbit; the position of the Sun with respect to the Moon orbit; and Sun, Moon, and Earth alignment. Our findings confirm concerns about textbook astronomy images, whose features may interfere with the identification of the relevant factors underlying the phenomena. Moreover, findings of this study suggest that affordances of the specially designed images may play an essential role in scaffolding meaningful understanding of the targeted phenomena. Implications for teaching through and learning from visual representations in astronomy education are briefly discussed.

[This paper is part of the Focused Collection on Astronomy Education Research.] In this paper we discuss the design and development of a learning progression (LP) to describe and interpret students’ understanding about stellar structure and evolution (SSE). The LP is built upon three content dimensions: hydrostatic equilibrium; composition and aggregation state; functioning and evolution. The data to build up the levels of the hypothetical LP (LP1) came from a 45-minute, seven-question interview, with 33 high school students previously taught about the topic. The questions were adapted from an existing multiple-choice instrument. Data were analyzed using Minstrell’s “facets” approach. To assess the validity of LP1, we designed a twelve-hour teaching module featuring paper-and-pencil tasks and practical activities to estimate the stellar structure and evolution parameters. Twenty high school students were interviewed before and after the activities using the same interview protocol. Results informed a revision of LP1 (LP2) and, in parallel, of the module. The revised module included supplementary activities corresponding to changes made to LP1. We then assessed LP2 with 30 high school students through the same interview, submitted before and after the teaching intervention. A final version of the LP (LP3) was then developed drawing on students’ emerging reasoning strategies. This paper contributes to research in science education by providing an example of the iterative development of the instruction required to support the student thinking that LPs’ levels describe. Concerning astronomy education research, our findings can inform suitable instructional activities more responsive to students’ reasoning strategies about stellar structure and evolution.