Maria Alessandra Sotgiu

Clinical characteristics of patients with familial amyotrophic lateral sclerosis carrying the pathogenic GGGGCC hexanucleotide repeat expansion of C9ORF72

A large hexanucleotide (GGGGCC) repeat expansion in the first intron of C9ORF72, a gene located on chromosome 9p21, has been recently reported to be responsible for ~40% of familial amyotrophic lateral sclerosis cases of European ancestry. The aim of the current article was to describe the phenotype of amyotrophic lateral sclerosis cases carrying the expansion by providing a detailed clinical description of affected cases from representative multi-generational kindreds, and by analysing the age of onset, gender ratio and survival in a large cohort of patients with familial amyotrophic lateral sclerosis. We collected DNA and analysed phenotype data for 141 index Italian familial amyotrophic lateral sclerosis cases (21 of Sardinian ancestry) and 41 German index familial amyotrophic lateral sclerosis cases. Pathogenic repeat expansions were detected in 45 (37.5%) patients from mainland Italy, 12 (57.1%) patients of Sardinian ancestry and nine (22.0%) of the 41 German index familial amyotrophic lateral sclerosis cases. The disease was maternally transmitted in 27 (49.1%) pedigrees and paternally transmitted in 28 (50.9%) pedigrees (P = non-significant). On average, children developed disease 7.0 years earlier than their parents [children: 55.8 years (standard deviation 7.9), parents: 62.8 (standard deviation 10.9); P = 0.003]. Parental phenotype influenced the type of clinical symptoms manifested by the child: of the 13 cases where the affected parent had an amyotrophic lateral sclerosis-frontotemporal dementia or frontotemporal dementia, the affected child also developed amyotrophic lateral sclerosis-frontotemporal dementia in nine cases. When compared with patients carrying mutations of other amyotrophic lateral sclerosis-related genes, those with C9ORF72 expansion had commonly a bulbar onset (42.2% compared with 25.0% among non-C9ORF72 expansion cases, P = 0.03) and cognitive impairment (46.7% compared with 9.1% among non-C9ORF72 expansion cases, P = 0.0001). Median survival from symptom onset among cases carrying C9ORF72 repeat expansion was 3.2 years lower than that of patients carrying TARDBP mutations (5.0 years; 95% confidence interval: 3.6-7.2) and longer than those with FUS mutations (1.9 years; 95% confidence interval: 1.7-2.1). We conclude that C9ORF72 hexanucleotide repeat expansions were the most frequent mutation in our large cohort of patients with familial amyotrophic lateral sclerosis of Italian, Sardinian and German ancestry. Together with mutation of SOD1, TARDBP and FUS, mutations of C9ORF72 account for ~60% of familial amyotrophic lateral sclerosis in Italy. Patients with C9ORF72 hexanucleotide repeat expansions present some phenotypic differences compared with patients with mutations of other genes or with unknown mutations, namely a high incidence of bulbar-onset disease and comorbidity with frontotemporal dementia. Their pedigrees typically display a high frequency of cases with pure frontotemporal dementia, widening the concept of familial amyotrophic lateral sclerosis.

C9ORF72 hexanucleotide repeat expansions in the Italian sporadic ALS population.

It has been recently reported that a large proportion of patients with familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are associated with a hexanucleotide (GGGGCC) repeat expansion in the first intron of C9ORF72. We have assessed 1757 Italian sporadic ALS cases, 133 from Sardinia, 101 from Sicily, and 1523 from mainland Italy. Sixty (3.7%) of 1624 mainland Italians and Sicilians and 9 (6.8%) of the 133 Sardinian sporadic ALS cases carried the pathogenic repeat expansion. None of the 619 regionally matched control samples (1238 chromosomes) carried the expansion. Twenty-five cases (36.2%) had behavioral FTD in addition to ALS. FTD or unspecified dementia was also detected in 19 pedigrees (27.5%) in first-degree relatives of ALS patients. Cases carrying the C9ORF72 hexanucleotide expansion survived 1 year less than cases who did not carry this mutation. In conclusion, we found that C9ORF72 hexanucleotide repeat expansions represents a sizeable proportion of apparent sporadic ALS in the Italian and Sardinian population, representing by far the most common mutation in Italy and the second most common in Sardinia.

Seasonal fluctuation of multiple sclerosis births in Sardinia

AbstractStudy results from different geographical areas provide some circumstantial evidence that, when compared with the general population, people who later in life develop multiple sclerosis (MS) have a pattern of birth excess numbers in spring and late summer, which may disclose an association with MS–predisposing environmental agents. To identify the presence of season–related cluster of MS birth in Sardinia we have designed a case–control study in the province of Sassari, Northern Sardinia, insular Italy, an area at veryhigh and increasing risk for MS. Mean birth incidence rate of people with MS (810 cases) on a threeand six–months basis were compared with that of two control populations: the MS unaffected siblings (1069), sharing genetic material with patients, and a representative number of births (247,612) of the general population of the study area. We found that the birth in months peaking in spring significantly represents one risk factor for future MS development. This seasonal deviation of MS births reveals an intriguing epidemiological overlap with common environmental agents, which may open a new scenario of hypothetical explanations for environmental factors perhaps affecting the CNS at the crucial time of myelination or shaping the newborn immune system.

ALS/FTD phenotype in two Sardinian families carrying both C9ORF72 and TARDBP mutations

Background In the isolated population of Sardinia, a Mediterranean island, ∼25% of ALS cases carry either a p.A382T mutation of the TARDBP gene or a GGGGCC hexanucleotide repeat expansion in the first intron of the C9ORF72 gene. Objective To describe the co-presence of two genetic mutations in two Sardinian ALS patients. Methods We identified two index ALS cases carrying both the p.A382T missense mutation of TARDBP gene and the hexanucleotide repeat expansion of C9ORF72 gene. Results The index case of Family A had bulbar ALS and frontemporal dementia (FTD) at 43. His father, who carried the hexanucleotide repeat expansion of C9ORF72 gene, had spinal ALS and FTD at 64 and his mother, who carried the TARDBP gene p.A382T missense mutation, had spinal ALS and FTD at 69. The index case of Family B developed spinal ALS without FTD at 35 and had a rapid course to respiratory failure. His parents are healthy at 62 and 63. The two patients share the known founder risk haplotypes across both the C9ORF72 9p21 locus and the TARDBP 1p36.22 locus. Conclusions Our data show that in rare neurodegenerative causing genes can co-exist within the same individuals and are associated with a more severe disease course.

Self-perceived physical functioning and health status among fully ambulatory multiple sclerosis patients

We investigated the self-perceived health status among multiple sclerosis (MS) patients with no or mild disability according to the Expanded Disability Status Scale (EDSS) and the impact of self-rated physical functioning. A sample of fully ambulatory (EDSS ≤ 3.5) consecutive patients with MS was included after screening for major cognitive impairment. The EDSS was used to measure nervous system signs or disability, and the self-rated health status was assessed using the SF-36 Health Survey. The normative SF-36 data for the general population of Italy were used for comparison. The 197 MS patients analyzed (150 women and 47 men) had significantly lower mean SF-36 scores than the general population, except for bodily pain. The scores did not differ significantly by gender. The same analysis performed on a subsample of 105 patients (79 women and 26 men) with minimal disability in one functional system (EDSS ≤ 2.0) yielded similar results. EDSS was weakly correlated with the physical functioning subscale and explained only 2% of the variance in the physical functioning subscale. The regression of the physical functioning subscale on the other seven SF-36 subscales was significantly lower among MS patients than in the general population for all subscales, except for role limitation due to physical health problems and social functioning. Neither disease course nor duration correlated significantly with SF-36 subscales. The SF-36 physical functioning subscale seemed to indicate physical functioning more sensitively than EDSS. These findings should encourage the implementation of specific strategies aimed at improving the quality of the self-perceived health status already in the early disease stage.

Essential trace elements in amyotrophic lateral sclerosis (ALS): Results in a population of a risk area of Italy

Sardinian (Italy) island population has a uniquely high incidence of amyotrophic lateral sclerosis (ALS). Essential trace element levels in blood, hair, and urine of ALS Sardinian patients were investigated in search of valid biomarkers to recognize and predict ALS. Six elements (Ca, Cu, Fe, Mg, Se, and Zn) were measured in 34 patients compared to 30 age- and sex-matched healthy controls by a validated method. Levels of Ca and Cu in blood and of Se and Zn in hair were significantly higher in ALS than in controls, while urinary excretion of Mg and Se was significantly decreased. The selected cut-off concentrations for these biomarkers may distinguish patients with or without ALS with sufficient sensitivity and specificity. Many positive (as Se-Cu and Se-Zn) and negative associations (as Ca-Mg and Ca-Zn) between elements suggested that multiple metals involved in multiple mechanisms have a role in the ALS degeneration.

Heavy Metals and Multiple Sclerosis in Sardinian Population (Italy)

The understanding of factors involved in the etiopathogenesis of Multiple Sclerosis (MS) is very important, especially in Sardinia (insular Italy) where one of the highest MS incidences in the world is consistently reported over time. There is evidence that some metals are implicated in the MS course and disability, and, a study was carried out to assess the concentration of Al, Cd, Cu, Fe, Mn, Pb, and Zn in the cerebrospinal fluid (CSF) of 51 Sardinian subjects (29 consecutive patients and 22 controls). In fact, any unbalance in the homeostasis of metals in the CSF might predispose to the cellular brain metal transport and accumulation giving rise to pathogenic lesions terminating in neurodegeneration. Samples were diluted with water and metals were quantified by sector field inductively coupled plasma mass spectrometry (SF-ICP-MS). Results revealed that none of the metals quantified in the CSF were able to distinguish the MS cases from controls and the different MS forms. Furthermore, sex, age, coffee, alcohol intake, and smoking did not represent risk factors for the disease. In light of this outcome, the reasons of the high incidence of MS in Sardinia may be more likely addressed to the susceptible genetic background that is easily triggered by other environmental agents. The results are the first data set on the elemental profile in the CSF of Sardinian patients and can be used for comparisons with possible abnormal contents in other pathologies.

Trace elements in ALS patients and their relationships with clinical severity

An exploratory study of trace elements in ALS and their relationships with clinical severity was detected. Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder that causes irreversible damage in humans, with the consequent loss of function of motoneurons (MNs), with a prognosis up to 5 years after diagnosis. Except to genetic rare cases it is not known the etiology of the disorder. Aim of our research is to investigate the possible role of heavy metals in the severity of the disease. In this study, by the use of plasma mass (ICP-MS), we have analyzed the content of essential and heavy metals such: Pb, Cd, Al, Hg, Mn, Fe, Cu, Zn, Se, Mg, and Ca, in blood, urine and hair of ALS patients and controls; moreover we divided the patients in two groups for disease severity and analyzed the difference among the groups, in order to study a possible involvement of metals in the severity of the damage. Our results suggest a protective role of Selenium, involved in protective antioxidant mechanisms, and a risk factor in the case of presence of Lead in blood. The levels of the other metals are not easy to interpret, because these may be due to life style and for essential metals a consequence of the disease condition, not a cause.

Cerebrotendinous xanthomatosis: recurrence of the CYP27A1 mutation p.Arg479Cys in Sardinia

Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disorder, due to mutations of the CYP27A1 gene, leading to cholestanol accumulation because of the sterol27-hydroxylase enzyme deficiency [1]. Treatment with chenodeoxycholic acid (CDCA) normalizes cholestanol and improves neurophysiological findings. Several mutations of the CYP27A1 gene are described in different ethnic groups [1], without genotype–phenotype correlations. We describe two unrelated Sardinian families sharing the same CYP27A1 mutation.

Osteological Markers of Malaria

Malaria is an acute and chronic disease caused by a parasitic protozoan, the Plasmodium. Five species infect humans and one of them, the Plasmodium falciparum, is the most attested in the past by biomolecular research (1). Recently the connection between malaria and various skeletal and dental lesions like Cribra Orbitalia (2, 3), Cribra Femuri and Hypoplasia (4) was supposed, already related with nutritional deficiency during development. The aim of this study is to verify this connection comparing osteological and biomolecular data. Samples from Nord-West of Sardinia were examined: four necropolis ranging from the Prenuragic period (3000 BC) to Middle Age (1400 AD). The necropolis underwent analysis using standard anthropological methods. To verify the presence of Plasmodium, samples from each necropolis were analyzed using an immune-chromatographic approach; only the fragment from Nuragic period showed a positive signal to Plasmodium falciparum. Cribra were evaluated according to a scale present in literature for Orbitalia (5) and Femuri (6); to better evaluate them, each pathological sample underwent radiographic and TC analysis. Crossing malaria and osteological data we can see that hypoplasia seems not to be related to malaria because it is absent when there is the Plasmodium falciparum; on the contrary, Cribra seems to be related to Plasmodium falciparum, especially Cribra Orbitalia were the most severe and the most common. Thanks to our data, we can say that osteological diseases like Cribra can be used to diagnose ancient cases of malaria.