Low specificity of anti-tissue transglutaminase antibodies in patients with primary biliary cirrhosis

The association between celiac disease (CD) and primary biliary cirrhosis (PBC) is well documented in medical literature; however, a high frequency of false positive results of the anti-transglutaminase (anti-tTG) test has been reported in patients with PBC. To verify if the positive results for anti-tTG autoantibody are false positives due to cross reactivity with mitochondrial antigens, we studied 105 adult patients affected with PBC, positive for anti-mitochondrial M2 antibodies. Anti-tTG IgA antibodies were studied by using six different immunoenzymatic assays that employ the tTG antigen obtained from different sources (human recombinant, placenta, red blood cells, and guinea pig liver). On the whole, 28 out of 105 PBC subjects tested positive for anti-tTG IgA antibodies, but only two were eventually found to be affected by CD; the other 26 were shown to be false positive. The specificity of the various antigenic substrates ranged from 88.5% of the human erythrocytes tTG to 97.1% of the human recombinant tTG. The results of this study showed that a true association between PBC and CD was present in only 2% of the patients and that, in most cases, the false positive results were attributable to the type of substrate utilized in the assay.

Genetic variation in the myeloperoxidase gene and cognitive impairment in multiple sclerosis

There is evidence that multiple sclerosis (MS) may associated with cognitive impairment in 25 to 40% of cases. The gene encoding myeloperoxidase (MPO) is involved in molecular pathways leading to beta-amyloid deposition. We investigated a functional biallelic (G/A) polymorphism in the promoter region (-463) of the MPO gene in 465 patients affected by MS, divided into 204 cognitively normal and 261 impaired. We did not find significant differences in allele or genotype distributions between impaired and preserved MS patients. Our findings suggest that MPO polymorphism is not a risk factor for cognitive impairment in MS.

Multiple Sclerosis Severity Score: Using disability and disease duration to rate disease severity

BACKGROUND

There is no consensus method for determining progression of disability in patients with multiple sclerosis (MS) when each patient has had only a single assessment in the course of the disease.

METHODS

Using data from two large longitudinal databases, the authors tested whether cross-sectional disability assessments are representative of disease severity as a whole. An algorithm, the Multiple Sclerosis Severity Score (MSSS), which relates scores on the Expanded Disability Status Scale (EDSS) to the distribution of disability in patients with comparable disease durations, was devised and then applied to a collection of 9,892 patients from 11 countries to create the Global MSSS. In order to compare different methods of detecting such effects the authors simulated the effects of a genetic factor on disability.

RESULTS

Cross-sectional EDSS measurements made after the first year were representative of overall disease severity. The MSSS was more powerful than the other methods the authors tested for detecting different rates of disease progression.

CONCLUSION

The Multiple Sclerosis Severity Score (MSSS) is a powerful method for comparing disease progression using single assessment data. The Global MSSS can be used as a reference table for future disability comparisons. While useful for comparing groups of patients, disease fluctuation precludes its use as a predictor of future disability in an individual.

A novel mutation (Thr116Ile) in the presenilin 1 gene in a patient with early-onset Alzheimer's disease

We report a novel presenilin 1 (PSN1) mutation (Thr116Ile) in a woman with early onset Alzheimer's disease (AD). This mutation was not found in 100 healthy controls, indicating that this is not a common polymorphism. The patient presented with forgetfulness at age 45, followed over the next 3 years by a worsening of the memory loss and frequent episodes of confusion and spatial disorientation. Neuroimaging studies were consistent with AD. The analysis of the family's pedigree showed that the proband was apparently the only member affected. Because the early death of several close relatives (i.e. the mother and the grandmother) and the demonstration that the father is not a mutation carrier, it is suggested that either a de novo mutation or a censor effect might have occurred. Our finding supports the indication that PSN1 mutations should be searched for in early-onset AD, particularly when a censor effect precludes a precise genetic analysis.

[Effectiveness of Troxerutin in association with Pycnogenol in the pharmacological treatment of venous insufficiency]

AIM

The purpose of our study was to assess the different effectiveness of Troxerutin in association with Pycnogenol compared to the effects obtainable with the same pharmacological principle in monotherapy in patients suffering from venous insufficiency.

METHODS

Seventy patients with venous insufficiency of the lower extremities at the first stages of the CEAP classification (Cs1,3; Es; As 1; invalidity score 2, clinical score 1-2) were selected and subdivided into 2 groups: one of 50 and one of 20. All patients reported the following symptoms either associated or in isolation: heaviness, cramps, pruritus and pain at palpation. Evaluation of the degree of venous insufficiency was carried out by means of echo-Doppler at recruitment. The 1st group received Troxerutin (470 mg) associated with Pycnogenol (20 mg) in a dose of 1 g/day per os for 60 days; the 2nd group Troxerutin alone (300 mg) in a dose of 2 tablets twice a day per os for 60 days. Controls were set up at 30 and 60 days from the start of treatment and after a period of 3 months from the end of treatment to assess the effects on the symptomatology over time. The effectiveness of the drugs on symptomatology reported by both groups was assessed by means of an analysis of the qualitative variation of the symptoms using the score-scales method: 3=severe; 2=moderate; 1=slight; 0=absent and this variation was expressed as a percentage decrease and analysed using Student's test.

RESULTS

The results of our study after 30 days of treatment highlighted a clinical improvement in all patients with the disappearance of symptoms (score from 3 to 1) in 50% of patients in the 1st group and in 35% in the 2nd with a peak of 96% in patients of the 1st group and 80% in the 2nd at the end of treatment (60 days). This result held stable in the course of follow-up for 96% of patients in the 1st group (p<0.001) and for 50% of those in the 2nd group (p<0.005).

CONCLUSION

Comparison between the 2 groups showed that the group which received Troxerutin associated with Pycnogenol reported greater therapeutic effectiveness than the control group as regards both the rapidity of disappearance of the symptoms and as regards maintenance of the cure obtained.

Course and prognosis in early-onset MS: comparison with adult-onset forms

OBJECTIVES

To establish the prognostic role of clinical and demographic factors in a hospital-based cohort of MS patients categorized by age at clinical onset and clinical course.

METHODS

Eighty-three patients with MS had a clinical onset of the disease in childhood (age <16 years; early-onset MS [EOMS]) and 710 in adult age (between 16 and 65 years; adult-onset MS [AOMS]). Patients were followed for a mean period of observation of 5 years. Univariate and multivariate analyses of clinical and demographic predictors for rapid progression and disability were performed using a stepwise Cox regression model with time-dependent covariates.

RESULTS

In EOMS, the Expanded Disability Status Scale (EDSS) evaluated at last clinical examination was lower than in AOMS, despite a longer disease duration. The probability to reach growth disability and progression was significantly lower in EOMS than in AOMS. Median times to reach EDSS score of 4 and secondary progression were longer in EOMS than in AOMS, but the age at both endpoints was significantly lower in EOMS. In EOMS and AOMS, an irreversible disability was related to a secondary progressive course, a sphincteric system involvement at onset, and an older age at onset (in EOMS only for the group >14 years); in AOMS, other unfavorable factors were a pyramidal involvement at onset and a high relapse frequency in the first 2 years. The risk of entering secondary progression was significantly influenced by a high number of relapses in EOMS and by a higher age at onset and a short interattack interval in AOMS.

CONCLUSION

A slower rate of progression of disease characterized EOMS patients, suggesting more plasticity to recover in developing CNS, but the early clinical manifestation cannot be considered a positive prognostic factor.

Technical procedure and ethical behaviour in biotechnologies of reproduction

BACKGROUND

The significant and constant progress of biotechnologies applied to sterility and infertility has induced a deeper reflection about bioethical problems. The analysis of only the biological dimension, about the results achieved and desirable future prospects, decreases, leaving out the anthropological dimension. It is therefore necessary to make reference to both the limits of the basic or applied research and to the usual welfare procedure. The aim, that the article sets itself, is to proceed to the bioethical analysis of the most significant topics of artificial insemination and assisted procreation; and it submits to anthropological evaluation the technical aspects, which characterize both the procreation techniques and the research prospects in this area.

METHODS

The bioethical analysis, used as a method of study and research, has availed itself of structured reasoning through the evaluation of the scientific, anthropological and legal-deontological dimensions, from an interdisciplinary point of view. The definition of the ethical norm, supported by authors, has been inferred from the analysis of the above-mentioned dimensions, considering the already known bioethical models. In particular, the authors analyse these topics through the model of ontologically based personalism, which suggests, and highlights, ethical norms, both as regards the basic and applied research and as regards usual welfare procedure, in opposition to models like moral sociologism, biologism, moral evolutionism and contractualism. From the beginning we defined "technical procedure" and "ethical behaviour", highlighting the interaction between them. We have made a distinction between artificial insemination, as a substitutive technique, and assisted procreation, as a facilitative technique. In addition through biological and anthropological results we have evaluated the embryo both ontologically and biologically. So we have defined "ontological and biological embryo status".

RESULTS AND CONCLUSIONS

The evaluation of the proposed topics for assisted procreation and against artificial insemination, the interaction between technical procedure and ethical behaviour, the acknowledgement of the embryo and personal dignity in every procedure are the principal results and the conclusions that we have arrived at, as regards the bioethical model of ontologically based personalism.

Identification of the Serum Complex Which Induces Cerebellar Granule Cell In Vitro Differentiation and Resistance to Excitatory Amino Acids

The protein complex promoting in vitro terminal differentiation of cerebellar granule cells has been isolated from rabbit serum. We designate the complex the neurite outgrowth and adhesion complex (NOAC). The apparent molecular weight, evaluated by gel filtration, is 80 - 100 kDa. Rat cerebellar granule cells cultured in NOAC exhibit much lower glial cell contamination and survive, in their differentiated state, much longer than in 10% foetal calf serum. While they bind tetanus toxin, express specific antigens such as synapsin I, synaptophisin and A2B5, and release [3H]d-aspartate in a fashion similar to that shown by cells cultured in foetal calf serum, they show a 60% reduction in the total number of kainate binding sites. Excitatory amino acid (EAA)-triggered and depolarization-stimulated calcium influx, measured in the presence of different agonists, is 50 - 80% lower in NOAC-cultured cells. NOAC cells are resistant to excitotoxic stimuli carried by EAAs or by depolarizing treatments with 50 mM KCl or 6 microM veratridine. The marked resistance of NOAC-cultured neurons to EAAs can be attributed to decreased calcium entry through EAA-coupled and voltage-gated calcium channels and possibly to other, as yet unidentified, phenotypic properties of these cells. These findings demonstrate that rabbit serum contains one or more polypeptide(s) endowed with the properties of promoting in vitro survival and differentiation of rat cerebellar granule cells and of conferring an EAA-resistant phenotype.

Prospective study of multiple sclerosis with early onset

Fifty-four subjects (36 females and 18 males) affected by clinically definite multiple sclerosis (MS) and with onset of the disease at 15 years of age or before were prospectively studied in five Italian MS centres. Female/male ratio was 4.7 in subjects with age > or = 12 years, suggesting a role of hormonal changes in triggering MS onset The mean follow-up duration was 10.9+/-5.6 years. The functional systems more frequently involved at onset were the pyramidal and brainstem (both in 28% of cases). The onset was monosymptomatic in 31 subjects (57%). The course was relapsing-remitting in 39 subjects (72%) and relapsing-progressive in 15 (28%). Disability was assessed by the Expanded Disability Status Scale (EDSS): the mean score after 8 years of follow up was 3.5 (+/-2.5). The score was <4 in 68% of cases, between 4 and 6 in 8% of cases, >6 in 24% of cases. Disability after 8 years was highly predicted by disability in the first year (p=0.008). There was a tendency to a worse prognosis in relation to the number of relapses in the first 2 years (p=0.08). The outcome was not influenced by the characteristics of symptoms at onset age and gender.

[General anesthesia and cervical anesthesia. What changes in carotid surgery]

Carotid surgery must be preventive; therefore cerebral protection procedures have been the centre of interest for a decade. Nowadays local cervical block anaesthesia seems to have changed the terms of the problem allowing achieve the aim of "no risk surgery". Therefore we considered our 16 year experience (352 carotids operated on 290 patients). Since 1990 we employed cervical block anaesthesia. In order to ratify as much as possible the two groups of comparison, considering that we adopted some exclusion criteria, we compared the results of the first hundred carotids that underwent surgery with general anaesthesia and the first hundred operated using cervical block anaesthesia. Since we adopted cervical block anaesthesia there was no need of intra-operative monitoring systems because we considered exclusively the patients' clinical answer to preclamping. The use of shunt decreased from 9% to 3%. Surgery performed in cervical block anaesthesia gives a positive impression. This is due to the fact that there is not only a significant reduction of the morbidity rate, especially from a neurologic point of view, but also a reduction of the post-operation hospital stay. Furthermore there is also a better organization of the surgical phases. Direct monitoring of the cerebral function allows a precise analysis of the peri-operatory neurological events. In conclusion our study suggests that cervical block anaesthesia allows clinical benefits for the patient as far as safety is concerned being also more convenient under the economic point of view.

Age at onset in multiple sclerosis

Age at onset of multiple sclerosis (MS) can vary from childhood to adult life. Many reports have been carried out over the years concerning the role of age at onset in determining the disease outcome. In a sporadic MS population of 1463 patients with homogeneous clinical and demographic features, derived from three Italian neurological centres (Bari, Cagliari and Sassari), we analysed the relative weights of current age and age at onset on disease severity according to the expanded disability status scale (EDSS) score, by fixing the disease duration. The results of present study demonstrate that clinical disability in MS is influenced by the patient's age (p < 0.01) and not by the age at onset. Therefore, these data do not confirm the hypothesis that an early age at onset should be considered a favourable prognostic factor of the disease outcome.

Axonal damage in multiple sclerosis plaques: a combined magnetic resonance imaging and 1H-magnetic resonance spectroscopy study

The purpose of this study was to compare magnetic resonance imaging (MRI) features and proton MR spectroscopy (1H-MRS) patterns of multiple sclerosis (MS) plaques in order to define the metabolic substrate in different lesion subtypes. Combined MRI and single-voxel 1H-MRS investigation was performed in 54 MS patients (47 relapsing remitting (RR) and seven secondary progressive (SP)). Sixty-seven MS lesions were selected. Thirty-seven lesions were Gadolinium (Gd) enhancing (nine isointense and 28 hypointense on pre-contrast T(1)-weighted scans) and 30 Gd unenhancing (six isointense and 24 hypointense on pre- and post-contrast T(1)-weighted scans). Choline (Cho), creatine (Cr), N-acetyl aspartate (NAA) and lactate were evaluated in 1H spectra acquired from MS plaques and from normal white matter (NWM) of 22 neurological controls. MS lesions of RR patients were characterized by a significant increase of Cho/Cr and decrease of NAA/Cr and NAA/Cho ratios. No significant metabolite changes were found in lesions of SP patients. Gd enhancing plaques showed lactate signal with higher frequency (37.8%) than Gd unenhancing plaques (16.7%) (p=0.04). A significant increase of Cho/Cr was found in Gd enhancing lesions when compared to controls (p<0.01), and to Gd unenhancing lesions (p<0.05). In particular, there was evidence of a significant increase of Cho/Cr in pre-contrast T(1) hypointense Gd enhancing lesions (p<0.01 vs. controls). The Gd unenhancing lesions (p<0.01), in particular the T(1) hypointense group (p<0.05), showed a significant decrease of NAA/Cr only when compared to controls. These data confirm that in vivo MRS indicates key pathological features of MS plaques. The increased Cho/Cr ratio found in Gd-enhancing plaques, in particular in the T(1) hypointense lesions, may reflect increased membrane cell turnover. The T(1) hypointense Gd unenhancing plaques better reflect axonal damage, as suggested by the decrease of NAA/Cr. Nevertheless, the lack of statistical differences in NAA/Cr between plaque subgroups suggests that axonal impairment might occur even in the early stages.

An attempt of identifying MS-associated loci as a follow-up of a genomic linkage study in the Italian population

Subsequent to a genomic linkage study on Sardinian and Continental Italian families, we considered the possibility that some of the tested microsatellite markers showed association to MS. Markers selected on the basis of the data obtained in the original set of 70 multiplex families were tested for MS association in an additional set of 154 simplex families. A limited set of markers were further tested on an additional set of 100 simplex families. The results indicate the presence of a putative MS gene in 19q13.13.

An interrupted 34-CAG repeat SCA-2 allele in patients with sporadic spinocerebellar ataxia

In spinocerebellar ataxia type 2 (SCA-2), a difference of three CAG repeats distinguishes normal alleles (14 to 31 repeats) from pathogenic alleles (34 to 57 repeats). All sequenced pathogenic alleles have a pure CAG repeat structure, whereas interrupted repeats have been seen exclusively in normal alleles. The authors present two patients with sporadic SCA with an interrupted 34-CAG repeat allele, (CAG)24(CAA)(CAG)9, who showed a phenotype compatible with SCA-2. The interrupted allele coding for a 34 pure polyglutamine tract may cause the SCA phenotype.

Changes of serum sICAM-1 and MMP-9 induced by rIFNbeta-1b treatment in relapsing-remitting MS

OBJECTIVE

To correlate changes in serum levels of intercellular adhesion molecule-1 (sICAM-1) and matrix metalloproteinases (MMP) with clinical and MRI evidence of disease activity in MS patients receiving treatment with interferon-beta (rIFNbeta)-1b.

BACKGROUND

rIFNbeta reduces the frequency of gadolinium-enhancing (Gd+) MRI in relapsing-remitting MS (RRMS). Its mechanism of action on improving the integrity of the blood-brain barrier remains unclear.

METHODS

sICAM-1 and MMP-9 and MMP-2 serum levels were longitudinally (24 months) investigated (ELISA; zymography) in correlation with the modifications of the integrated area under the curve of Expanded Disability Status Scale scores normalized to entry baseline (deltaEDSS AUC) and of GD+ MRI scans, and with neutralizing antibodies (NAB) to rIFNbeta-1b production (MxA) in 36 RRMS patients.

RESULTS

During the first 12 months of treatment, levels of sICAM-1 increased and MMP-9 decreased significantly. After 12 months, levels returned toward baseline. Levels of sICAM-1 and MMP-9 were significantly negatively correlated. MMP-2 levels did not change significantly during the same period. During the second semester of the study, deltaEDSS AUC was significantly reduced. The percentage of patients with Gd+ MRI decreased significantly in the first (33%), second (29%), third (20%), and fourth (28%) semesters of treatment compared to baseline (62%). The NAB+ patients (14%) tended to have lower sICAM-1 levels at the ninth month; a higher MMP-9 activity at the sixth, 12th, and 18th months; and a greater deltaEDSS AUC in the third semester of treatment in comparison with the NAB- patients.

CONCLUSIONS

These results show that rIFNbeta-1b therapy increases sICAM-1 serum levels and reduces serum MMP-9 activity.

[Congenital diaphragmatic hernia. Prenatal diagnosis and neonatal outcome]

BACKGROUND

The objective of this study is to determine the management and the outcome of 17 cases of congenital diaphragmatic hernia observed, and to compare the results with the literature data.

METHODS

The study was made between June 1994 and June 1998 in the Department of Obstetrics and Gynecology of the University of Naples Federico II and it collected 17 pregnant women with diagnosed or suspected congenital diaphragmatic hernia, referred to our diagnostic unit from other institutes: between 18 and 37 weeks' gestation, a detailed ultrasound examination and an echocardiography were performed to confirm the diagnosis, to establish the site and contents of the hernia exactly and to detect associated structural malformations. Fetal kariotyping was made in 7 cases. When the women decided to continue pregnancy, or the legal limit for termination of pregnancy was exceeded, the pregnancy was monitored with ultrasound examination, delivery took place in our department and the baby was transferred to an intensive care unit.

RESULTS

Ultrasound examination led to the diagnosis of 14 postero-lateral left-sided diaphragmatic hernias (82.3%), 1 antero-lateral left-sided (5.9%), 1 bilateral postero-lateral sided (5.9%) and 1 diaphragmatic eventration (5.9%). Associated structural malformation were diagnosed in 4 fetuses (27%). In 1 case only (14.3% of examinated kariotyping) an abnormal result was found. Five pregnancies (29.4%) were terminated, 2 (11.7%) are still going on and 10 fetuses (58.9%) were born alive: 5 fetuses (50%) died in the first days of life before surgical intervention, 2 (40% of operated children and 20% of born alive) died after the operation and 3 (60% of operated children and 30% of born alive) are actually alive and in good health. The total postnatal mortality was 70% and 40% after operation.

CONCLUSIONS

From the analysis of these data and from the international literature the conclusion is drawn that congenital diaphragmatic hernia is associated with a high postnatal mortality, although potentially it can be corrected with surgery: a better postnatal management and a better knowledge of evaluable in uterus prognostic factors are necessary to improve postnatal outcome.

[Cystic adenomatoid malformation of the lung at the fetal stage. Ultrasonographic diagnosis and counseling]

BACKGROUND

The aim of this study was to report the series of cystic malformation of the lung (CAML) detected at the Center for Prenatal Diagnosis of the University of Naples Federico II and compare the data with the current literature.

METHODS

In the period 1994-1997, ten cases of CAML have been detected at our unit. For each case, the following parameters were recorded: size of the cysts (according to the Stocker classification), side, presence of mediastinal shift, hydrops. For confirmation, necropsies and post natal files were sought.

RESULTS

CAML was type I in 3 cases, type II in 3, and type III in 4 cases. mediastinal shift was present in 7 cases, hydrops in 2 and bilateral renal agenesis in 1. Seven cases underwent termination of pregnancy, 2 are currently alive and thriving after surgery and one pregnancy is ongoing at 36 weeks of gestation. The diagnosis was straightforward in all cases, and there were no problems of differential diagnosis.

CONCLUSIONS

From an analysis of the data published in recent literature, it can be affirmed that hydrops but not mediastinal shift have negative prognostic significance. The abortion rate of 70% in our series, including 4 cases with a good prognosis, is somewhat frustrating. This figure underlines the need for a multidisciplinary counseling in which the pediatric surgeon, the psychologist and the sonographer may support the couple in overcoming the stress related to the acknowledgement of the lesion in order to reach the final decision about the outcome of the pregnancy.

Prenatal findings in trisomy 16q of paternal origin

A 34-year-old pregnant woman was referred at 30 weeks of gestation with suspected fetal congenital heart disease. On prenatal ultrasound the following anomalies were detected: intra-uterine growth retardation, micrognathia, coarctation of the aorta with ventricular and atrial septal defects, ambiguous external genitalia, and clinodactyly of one hand with adducted thumb. Prenatal karyotyping was offered but refused by the patient. The fetus was delivered by Caesarean section due to fetal distress at 36 weeks of gestation. The neonate, weighing 2150 g was transferred to the neonatal intensive care unit, where he died 10 days later. The karyotype from peripheral blood lymphocytes was 46,XY+der(20)t(16;20)(q12.1;p13)pat. The maternal karyotype was unremarkable, whereas the father had the translocation t(16;20)(q12.1;p13). Necropsy confirmed all the prenatal findings. These are discussed together with the implications of the chromosomal diagnosis and the pertinent literature is reviewed.

Linkage analysis of multiple sclerosis with candidate region markers in Sardinian and Continental Italian families

Previous genome screens in multiple sclerosis have shown some evidence of linkage in scattered chromosomal regions. Although in no case the evidence of each single study was compelling and although in general the linkage 'peaks' of the different studies did not coincide, some regions can be considered likely candidates for the presence of MS risk genes because of the clustering of MLS scores and homology with eae loci. We performed a linkage analysis of markers in these regions and of intragenic markers of some individual candidate genes (HLA-DRB1, CTLA-4, IL9, APOE, BCL2, TNFR2). For the first time, Southern European populations were targeted, namely Continental Italians and Sardinians. A total of 69 multiplex families were typed for 67 markers by a semi-automatic fluorescence-based assay. Results were analysed for linkage by two non-parametric tests: GENEHUNTER and SimIBD. In general, the linkage scores obtained were low, confirming the conclusion that no gene is playing a major role in the disease. However, some markers, in 2p11, 3q21.1, 7p15.2 and 22q13.1 stood out as promising since they showed higher scores with one or the other test. This stimulates further association analysis of a large number of simplex families from the same populations.

Comparison of clinical and demographic features between affected pairs of Italian multiple sclerosis multiplex families; relation to tumour necrosis factor genomic polymorphisms

We conducted a comparative analysis of clinical and demographic findings between pairs of relatives (36 sibling and 9 parent/child), concordant for Multiple Sclerosis (MS), from 40 MS Italian Multiplex families. A genetic TNF (alpha and beta) loci typing in 51 affected and 69 healthy relatives belonging to 25 of these families was also performed. The sib pairs resulted significantly concordant for age at onset (r=0.414, P<0.013), Progression Index (r=0.34, P<0.05) and sensory symptoms at onset (k=0.37), and significantly not concordant for sex (k=-0.37), whereas no concordance was found for year at onset and disease course. The only significant result in the small group of parent/child pairs was that parents developed MS at an age of 18.74 years significantly (P=0.020) greater than their children. Genomic analysis identified 13 variants of TNF-a alleles, 7 of TNF-b, 6 of TNF-d and 3 of TNF-e. No differences in the frequencies of the various TNF alleles were observed between affected and healthy relatives. The two-point lod-score analysis of the TNF locus showed not significant or negative results for the TNFalpha loci and slightly positive results (Zmax=0.4 at theta=0.2 cM) for the TNFbeta-b locus in the lowest penetrance dominant model. The Sib pair analysis, using combined TNFalpha and TNFbeta haplotypes, demonstrated a TNF allele sharing between affected sib-pairs which did not exceed the expected 50%. These results suggest that genetic factors may partially influence the disease onset and the progression rate in sibling pairs. A recall bias and/or an 'anticipation phenomenon' could explain the development of MS at an older age in parents than in their children. In this small-sized cohort of MS Italian families no significant associations were confirmed between TNF polymorphism and MS.