Volume 1 (2017): Issue s2 (December 2017)
MAGI group activity - Research, diagnosis and treatment of genetic and rare diseases

MAGI is concerned with research and diagnosis of rare genetic diseases. It has been operating since 2006 in Italy and abroad. Today it has three centers in Italy, including a medical genetics laboratory specialized in next generation sequencing in Bolzano, a medical genetics laboratory specialized in MLPA in Rovereto (Trento) and a genetic diseases information center at San Felice del Benaco (Brescia). MAGI has also invested outside Italy, setting up non-profit genetics laboratories in countries such as Albania, Russia and in the near future, Kazakhstan.

The major structural proteins of the vascular wall are collagen and elastin. Genetic connective tissue diseases lead to degeneration, aneurysms and spontaneous dissection or rupture of arteries. The best-known are Marfan syndrome, vascular Ehlers-Danlos syndrome (type IV), Loeys-Dietz syndrome and familial aortic aneurysms and dissections. Objective. This review addresses the current status of endovascular treatment options for major connective tissue diseases. The treatment of choice for patients who are mostly affected at a young age is primarily conservative or open repair. There is only limited evidence in favour of endovascular aortic repair (EVAR) of abdominal aneurysms or thoracic endovascular aortic repair (TEVAR) because disease progression and dilation leads to secondary endoleaks and high reintervention rates with uncertain long-term results. There is therefore consensus that EVAR and TEVAR should be limited to exceptional cases and emergency situations in patients with genetic aortic diseases.

Respiration is controlled by the complex orchestration of central nervous system centers, peripheral chemoreceptors and muscles of respiration and is shaped by complex ontogenetic factors. Genetic defects can interfere with these factors, leading to the development of disorders of central control of breathing. Here, we briefly discuss the most important of these rare genetic syndromes: congenital central hypoventilation syndrome (CCHS), Rett’s syndrome (RTT), Prader-Willi syndrome (PWS) and Joubert syndrome. All these conditions are severe neurodevelopmental pathologies that can also involve other organs and systems and have specific genetic backgrounds that if correctly identified can enable better prognostic counseling of patients and/or caregivers. Treatment of disordered breathing is often necessary to counteract the life-threatening problems typical of CCHS and those that complicate the clinical course of RTT, PWS and Joubert syndrome.

Molecular diagnosis relieves patients of uncertainty, aids informed decisions about health and reproductive choices, and helps them join clinical trials or access available therapy. Genetic testing by next generation sequencing (NGS) is the suggested choice for a wide variety of disorders with heterogeneous phenotypes, alleles and loci. The development of a NGS service at MAGI Balkans, through the support of a partner, increases the availability of forefront genetic testing in Albania with great advantages for patients and their families. Here we report the NGS tests performed in collaboration with MAGI Euregio, Italy, for the diagnosis of rare genetic disease in seven probands and their families. The diseases/manifestations included ichthyosis, familial adenomatous polyposis, diabetes, syndromic craniosynostosis, fronto-temporal dementia, fragile X syndrome and ataxia. We obtained an overall detection rate of 57%. For 4/7 probands we identified a pathogenic or likely pathogenic variant, while for the others, the results did not completely explain the phenotype. All variants were confirmed by Sanger sequencing. Segregation of the variant with the affected phenotype was also evaluated.

Amyotrophic lateral sclerosis, also known as motor neuron disease or Lou Gehrig’s disease, is an adult-onset neurodegenerative disease that targets motor neurons in the spinal cord, cortex and brain stem. Selective degeneration of corticospinal (upper) and spinal (lower) motor neurons manifests as a linear decline in muscular function, eventually resulting in paralysis, speech and swallowing deficits and death, usually from impaired respiratory function, over a time course of approximately 3-5 years.

Lesch-Nyhan Disease (LND) is a rare X-linked genetic disease with hypoxanthine-guanine phosphoribosyltransferase (HGPRT) deficiency, due to mutation in the encoding gene, located on the X-chromosome. LND patients exhibit hyperuricemia with stones due to unrecycled purine accumulation and increased synthesis, and a devastating neurological syndrome with dystonia and self-injurious behaviour, choreoathetosis and spasticity. In spite of biochemical and molecular research, the fine connection between the neurological syndrome and HGPRT deficiency is still unclear, though there is consensus regarding brain neurotransmitter dysfunction with few dopaminergic neuron terminals in the striatum. The rarity of the disease makes it difficult to obtain homogeneous population of patients to study. The aim of this paper is to contribute to the understanding of the connection between genotype and phenotype in a cohort of Italian patients, to propose a reliable method of identifying carrier women in affected families, and to provide evidence of a possible link between HGPRT deficiency and altered adenosinergic and serotonergic neurotransmission. Biochemical and mutation analysis is reported in 28 LNS Italian patients from 25 families, with virtually no HGPRT activity and typical LNS phenotype. Genetic analysis identified 24 HPRT mutations, nine of which had never previously been reported, and no mutation hotspots. Carrier females were identified by a new semiquantitative real-time PCR. Studies performed by real-time PCR on knockout mice demonstrated altered adenosinergic and serotonergic pathways, with greatly increased ADORA1A receptor expression, slightly decreased ADORA2A expression and unchanged ADORA2B expression. Increased HTRC2 expression with no significant difference in mRNA editing suggested serotonergic involvement. The different approaches used allowed us to study certain aspects of LND, focusing on mutation analysis in patients and carriers and on simultaneous analysis of biochemical and genetic features. Mouse models elucidated the possible involvement of adenosine and serotonine receptors in the neurotransmission aberration occurring in HGPRT deficiency.

Primary lymphedema can be familial (in which more than one member of the same family has a lymphedema phenotype), syndromic (in which lymphedema is one symptom of a complex clinical syndrome) or sporadic (in which an isolated family member has lymphedema). All types of lymphedema are determined by genetic alteration of one or more genes. Not all the genes involved are known.

A goal of regenerative medicine is to repair and regenerate damaged cells, tissues, and organs and ultimately restore function. Regeneration can be obtained by cell replacement or by stimulating the body’s own repair mechanisms. It requires a favorable microenvironment so that regenerative signals can stimulate resident stem/stromal cells. Regeneration is only possible after resolution of injury-induced inflammation. Immune response may be aggravated in degenerative, inflammation-based diseases. In this mini-review we discuss how cells isolated from the amniotic membrane of human term placentas and their derivatives, such as conditioned cell culture medium, can help resolve many diseases characterized by altered immune response by acting on different inflammatory mediators. Amniotic cells and derivatives have a wide spectrum of immunomodulatory properties that help trigger tissue regeneration. They can promote resolution of injury-related inflammation by reducing pro-inflammatory signals and favoring anti-inflammatory immune components. The multifaceted, immunomodulatory properties of amniotic membrane-derived cells and derivatives make them attractive for a variety of applications, especially in diseases with an exacerbated immune response, such as degenerative, inflammatory- based diseases.

Approximately 15% of couples in western countries have infertility problems. Identification of genetic alterations responsible for infertility is important for therapy and to avoid transmission of genetic abnormalities that could impair the health of offspring, especially for couples with idiopathic infertility and those undergoing assisted reproductive techniques (ART). The aim of this review is to summarize the main genetic tests to offer to infertile couples during diagnostic work-up and in cases of ART, considering future directions of risk assessment in the field of reproductive medicine. Before offering a genetic test to an infertile couple, it is crucial to characterize their clinical and hormonal profile. Genetic testing should only be carried out when appropriate, that is when clinical and family history suggest a genetic cause of infertility. The genetic tests to offer to infertile couples must be targeted at infertility and should always consider the cost/benefit ratio. No causative genes have been identified for certain conditions, making clinical genetic testing impractical. Next generation sequencing (NGS) is a powerful tool for the identification of pathological mutations and for discovering new disease-associated loci in the field of reproduction. Comprehensive multigene panels for infertile risk assessment could simplify the diagnostic and therapeutic process. The main limitation is interpretation of the enormous amount of NGS data, since the clinical role and biological implications of variants, especially those of unknown significance, are still unclear.