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Congenital hypogonadotropic hypogonadism (cHH)/Kallmann syndrome (KS) is a rare genetic disorder with variable penetrance and a complex inheritance pattern. Consequently, it does not always follow Mendelian laws. More recently, digenic and oligogenic transmission has been recognized in 1.5–15% of cases. We report the results of a clinical and genetic investigation of five unrelated patients with cHH/KS analyzed using a customized gene panel. Patients were diagnosed according to the clinical, hormonal, and radiological criteria of the European Consensus Statement. DNA was analyzed using next-generation sequencing with a customized panel that included 31 genes. When available, first-degree relatives of the probands were also analyzed to assess genotype–phenotype segregation. The consequences of the identified variants on gene function were evaluated by analyzing the conservation of amino acids across species and by using molecular modeling. We found one new pathogenic variant of the CHD7 gene (c.576T>A, p.Tyr1928) and three new variants of unknown significance (VUSs) in IL17RD (c.960G>A, p.Met320Ile), FGF17 (c.208G>A, p.Gly70Arg), and DUSP6 (c.434T>G, p.Leu145Arg). All were present in the heterozygous state. Previously reported heterozygous variants were also found in the PROK2 (c.163del, p.Ile55*), CHD7 (c.c.2750C>T, p.Thr917Met and c.7891C>T, p.Arg2631*), FLRT3 (c.1106C>T, p.Ala369Val), and CCDC103 (c.461A>C, p.His154Pro) genes. Molecular modeling, molecular dynamics, and conservation analyses were performed on three out of the nine variants identified in our patients, namely, FGF17 (p.Gly70Arg), DUSP6 (p.Leu145Arg), and CHD7 p.(Thr917Met). Except for DUSP6, where the L145R variant was shown to disrupt the interaction between β6 and β3, needed for extracellular signal-regulated kinase 2 (ERK2) binding and recognition, no significant changes were identified between the wild-types and mutants of the other proteins. We found a new pathogenic variant of the CHD7 gene. The molecular modeling results suggest that the VUS of the DUSP6 (c.434T>G, p.Leu145Arg) gene may play a role in the pathogenesis of cHH. However, our analysis indicates that it is unlikely that the VUSs for the IL17RD (c.960G>A, p.Met320Ile) and FGF17 (c.208G>A, p.Gly70Arg) genes are involved in the pathogenesis of cHH. Functional studies are needed to confirm this hypothesis.

Lymphedema is a chronic inflammatory disorder caused by ineffective fluid uptake by the lymphatic system, with effects mainly on the lower limbs. Lymphedema is either primary, when caused by genetic mutations, or secondary, when it follows injury, infection, or surgery. In this study, we aim to assess to what extent the current genetic tests detect genetic variants of lymphedema, and to identify the major molecular pathways that underlie this rather unknown disease. We recruited 147 individuals with a clinical diagnosis of primary lymphedema and used established genetic tests on their blood or saliva specimens. Only 11 of these were positive, while other probands were either negative (63) or inconclusive (73). The low efficacy of such tests calls for greater insight into the underlying mechanisms to increase accuracy. For this purpose, we built a molecular pathways diagram based on a literature analysis (OMIM, Kegg, PubMed, Scopus) of candidate and diagnostic genes. The PI3K/AKT and the RAS/MAPK pathways emerged as primary candidates responsible for lymphedema diagnosis, while the Rho/ROCK pathway appeared less critical. The results of this study suggest the most important pathways involved in the pathogenesis of lymphedema, and outline the most promising diagnostic and candidate genes to diagnose this disease.

Guanylate cyclase-activating protein 1 (GCAP1), encoded by the GUCA1A gene, is a neuronal calcium sensor protein involved in shaping the photoresponse kinetics in cones and rods. GCAP1 accelerates or slows the cGMP synthesis operated by retinal guanylate cyclase (GC) based on the light-dependent levels of intracellular Ca2+, thereby ensuring a timely regulation of the phototransduction cascade. We found a novel variant of GUCA1A in a patient affected by autosomal dominant cone dystrophy (adCOD), leading to the Asn104His (N104H) amino acid substitution at the protein level. While biochemical analysis of the recombinant protein showed impaired Ca2+ sensitivity of the variant, structural properties investigated by circular dichroism and limited proteolysis excluded major structural rearrangements induced by the mutation. Analytical gel filtration profiles and dynamic light scattering were compatible with a dimeric protein both in the presence of Mg2+ alone and Mg2+ and Ca2+. Enzymatic assays showed that N104H-GCAP1 strongly interacts with the GC, with an affinity that doubles that of the WT. The doubled IC50 value of the novel variant (520 nM for N104H vs. 260 nM for the WT) is compatible with a constitutive activity of GC at physiological levels of Ca2+. The structural region at the interface with the GC may acquire enhanced flexibility under high Ca2+ conditions, as suggested by 2 μs molecular dynamics simulations. The altered interaction with GC would cause hyper-activity of the enzyme at both low and high Ca2+ levels, which would ultimately lead to toxic accumulation of cGMP and Ca2+ in the photoreceptor outer segment, thus triggering cell death.

Blue cone monochromatism (BCM) is an X-linked recessive cone dysfunction disorder caused by mutations in the OPN1LW/OPN1MW gene cluster, encoding long (L)- and middle (M)-wavelength-sensitive cone opsins. Here, we report on the unusual clinical presentation of BCM caused by a novel mutation in the OPN1LW gene in a young man. We describe in detail the phenotype of the proband, and the subclinical morpho-functional anomalies shown by his carrier mother. At a clinical level, the extensive functional evaluation demonstrated in the proband the M/L cone affection and the sparing of S-cone function, distinctive findings of BCM. Interestingly, spectral-domain optical coherence tomography showed the presence of foveal hypoplasia with focal irregularities of the ellipsoid layer in the foveal area, reported to be associated with some cases of cone-rod dystrophy and achromatopsia. At a molecular level, we identified the novel mutation c.427T > C p.(Ser143Pro) in the OPN1LW gene and the common missense mutation c.607T > C (p.Cys203Arg) in the OPN1MW gene. In addition, we discovered the c.768-2_769delAGTT splicing variant in the GPR143 gene. To our knowledge, this is the first case of foveal hypoplasia in a BCM patient and of mild clinical affection in a female carrier caused by the concomitant effect of variants in OPN1LW/OPN1MW and GPR143 genes, thus as the result of the simultaneous action of two independent genetic defects.

Guanylate cyclase-activating protein 1 (GCAP1) is involved in the shutdown of the phototransduction cascade by regulating the enzymatic activity of retinal guanylate cyclase via a Ca2+/cGMP negative feedback. While the phototransduction-associated role of GCAP1 in the photoreceptor outer segment is widely established, its implication in synaptic transmission to downstream neurons remains to be clarified. Here, we present clinical and biochemical data on a novel isolate GCAP1 variant leading to a double amino acid substitution (p.N104K and p.G105R) and associated with cone dystrophy (COD) with an unusual phenotype. Severe alterations of the electroretinogram were observed under both scotopic and photopic conditions, with a negative pattern and abnormally attenuated b-wave component. The biochemical and biophysical analysis of the heterologously expressed N104K-G105R variant corroborated by molecular dynamics simulations highlighted a severely compromised Ca2+-sensitivity, accompanied by minor structural and stability alterations. Such differences reflected on the dysregulation of both guanylate cyclase isoforms (RetGC1 and RetGC2), resulting in the constitutive activation of both enzymes at physiological levels of Ca2+. As observed with other GCAP1-associated COD, perturbation of the homeostasis of Ca2+ and cGMP may lead to the toxic accumulation of second messengers, ultimately triggering cell death. However, the abnormal electroretinogram recorded in this patient also suggested that the dysregulation of the GCAP1–cyclase complex further propagates to the synaptic terminal, thereby altering the ON-pathway related to the b-wave generation. In conclusion, the pathological phenotype may rise from a combination of second messengers’ accumulation and dysfunctional synaptic communication with bipolar cells, whose molecular mechanisms remain to be clarified.

Forkhead-box C2 (FOXC2) is a transcription factor involved in lymphatic system development. FOXC2 mutations cause Lymphedema-distichiasis syndrome (LD). Recently, a natural antisense was identified, called lncRNA FOXC2-AS1, which increases FOXC2 mRNA stability. No studies have evaluated FOXC2 and FOXC2-AS1 blood expression in LD and healthy subjects. Here, we show that FOXC2 and FOXC-AS1 expression levels were similar in both controls and patients, and a significantly higher amount of both RNAs was observed in females. A positive correlation between FOXC2 and FOXC2-AS1 expression was found in both controls and patients, excluding those with frameshift mutations. In these patients, the FOXC2-AS1/FOXC2 ratio was about 1:1, while it was higher in controls and patients carrying other types of mutations. The overexpression or silencing of FOXC2-AS1 determined a significant increase or reduction in FOXC2 wild-type and frameshift mutant proteins, respectively. Moreover, confocal and bioinformatic analysis revealed that these variations caused the formation of nuclear proteins aggregates also involving DNA. In conclusion, patients with frameshift mutations presented lower values of the FOXC2-AS1/FOXC2 ratio, due to a decrease in FOXC2-AS1 expression. The imbalance between FOXC2 mRNA and its lncRNA could represent a molecular mechanism to reduce the amount of FOXC2 misfolded proteins, protecting cells from damage.

Background The rapid spread of genome‐wide next‐generation sequencing in the molecular diagnosis of rare genetic disorders has produced increasing evidence of multilocus genomic variations in cases with a previously well‐characterized molecular diagnosis. Here, we describe two patients with a rare combination of skeletal abnormalities and retinal dystrophy caused by variants in the SLC26A2 and ABCA4 genes, respectively, in a family with parental consanguinity. Methods Next‐generation sequencing and Sanger sequencing were performed to obtain a molecular diagnosis for the retinal and skeletal phenotypes, respectively. Results Genetic testing revealed that the sisters were homozygous for the p.(Cys653Ser) variant in SLC26A2 and heterozygous for the missense p.(Pro68Leu) and splice donor c.6386+2C>G variants in ABCA4. Segregation analysis confirmed the carrier status of the parents. Conclusion Despite low frequency of occurrence, the detection of multilocus genomic variations in a single disease gene‐oriented approach can provide accurate diagnosis even in cases with high phenotypic complexity. A targeted sequencing approach can detect relationships between observed phenotypes and underlying genotypes, useful for clinical management., Sequencing techniques advancement enhances multilocus genomic variations detection. Here we described two rare cases of skeletal dysplasia with ophthalmic manifestations. Genetic testing revealed that the proband and her sister were affected by two rare diseases, the recessive multiple epiphyseal dysplasia and stargardt syndrome. We also provided a summary of drugs discovery for both the conditions.

The small Ras-related GTPase Rab-28 is highly expressed in photoreceptor cells, where it possibly participates in membrane trafficking. To date, six alterations in the RAB28 gene have been associated with autosomal recessive cone-rod dystrophies. Confirmed variants include splicing variants, missense and nonsense mutations. Here, we present a thorough phenotypical and genotypical characterization of five individuals belonging to four Italian families, constituting the largest cohort of RAB28 patients reported in literature to date. All probands displayed similar clinical phenotype consisting of photophobia, decreased visual acuity, central outer retinal thinning, and impaired color vision. By sequencing the four probands, we identified: a novel homozygous splicing variant, two novel nonsense variants in homozygosis, a novel missense variant in compound heterozygous state with a previously reported nonsense variant. Exhaustive molecular dynamics simulations of the missense variant p.(Thr26Asn) in both its active and inactive states revealed an allosteric structural mechanism that impairs the binding of Mg2+, thus decreasing the affinity for GTP. The impaired GTP-GDP exchange ultimately locks Rab-28 in a GDP-bound inactive state. The loss-of-function mutation p.(Thr26Asn) was present in a compound heterozygosis with the nonsense variant p.(Arg137*), which does not cause mRNA-mediated decay, but is rather likely degraded due to its incomplete folding. The frameshift p.(Thr26Valfs4*) and nonsense p.(Leu13*) and p.(Trp107*) variants, if translated, would lack several key structural components necessary for the correct functioning of the encoded protein.

Lipedema is an often underdiagnosed chronic disorder that affects subcutaneous adipose tissue almost exclusively in women, which leads to disproportionate fat accumulation in the lower and upper body extremities. Common comorbidities include anxiety, depression, and pain. The correlation between mood disorder and subcutaneous fat deposition suggests the involvement of steroids metabolism and neurohormones signaling, however no clear association has been established so far. In this study, we report on a family with three patients affected by sex-limited autosomal dominant nonsyndromic lipedema. They had been screened by whole exome sequencing (WES) which led to the discovery of a missense variant p.(Leu213Gln) in AKR1C1, the gene encoding for an aldo-keto reductase catalyzing the reduction of progesterone to its inactive form, 20-&alpha, hydroxyprogesterone. Comparative molecular dynamics simulations of the wild-type vs. variant enzyme, corroborated by a thorough structural and functional bioinformatic analysis, suggest a partial loss-of-function of the variant. This would result in a slower and less efficient reduction of progesterone to hydroxyprogesterone and an increased subcutaneous fat deposition in variant carriers. Overall, our results suggest that AKR1C1 is the first candidate gene associated with nonsyndromic lipedema.

FOXC2 is a member of the human forkhead-box gene family and encodes a regulatory transcription factor. Mutations in FOXC2 have been associated with lymphedema distichiasis (LD), an autosomal dominant disorder that primarily affects the limbs. Most patients also show extra eyelashes, a condition known as distichiasis. We previously reported genetic and clinical findings in six unrelated families with LD. Half the patients showed missense mutations, two carried frameshift mutations and a stop mutation was identified in a last patient. Here we analyzed the subcellular localization and transactivation activity of the mutant proteins, showing that all but one (p.Y109*) localized to the nucleus. A significant reduction of transactivation activity was observed in four mutants (p.L80F, p.H199Pfs*264, p.I213Tfs*18, p.Y109*) compared with wild type FOXC2 protein, while only a partial loss of function was associated with p.V228M. The mutant p.I213V showed a very slight increase of transactivation activity. Finally, immunofluorescence analysis revealed that some mutants were sequestered into nuclear aggregates and caused a reduction of cell viability. This study offers new insights into the effect of FOXC2 mutations on protein function and shows the involvement of aberrant aggregation of FOXC2 proteins in cell death.

Lymphatic malformations (LMs) show phenotypic variability, as well as clinical and genetic heterogeneity. Inheritance is autosomal dominant, recessive or X-linked and major genes involved in predisposition for LMs are continuously being discovered. The literature also indicates that somatic mutations play an important role in the development of LMs. In fact, activating somatic mutations in PIK3CA have been reported in lymphatic endothelial cells obtained from patients with different kinds of LM. This Utility Gene Test was developed on the basis of an analysis of the literature and existing diagnostic protocols. It is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Cystic hygroma (CH) is characterized by abnormal accumulation of fluid in the region of the fetal neck and is a major anomaly associated with aneuploidy. Morphologically characterized by failure of the lymphatic system to communicate with the venous system in the neck, the clinical manifestations of CH depend on its size and location. Incidence is estimated at one case per 6000-16,000 live births. CH has autosomal dominant or autosomal recessive inheritance. This Utility Gene Test was developed on the basis of an analysis of the literature and existing diagnostic protocols. It is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Marfan-like disorders are inherited conditions with features resembling Marfan syndrome but without a pathogenic variant in FBN1, and/or without a clinical diagnosis of Marfan syndrome according to the Revised Ghent criteria, and/or with a pathogenic variant in a different disease gene. Marfan-like disorders are clinically and genetically heterogeneous and have variable prognosis. They may have autosomal dominant or autosomal recessive patterns of inheritance. The prevalence of most Mar-fan-like disorders is unknown. This Utility Gene Test was prepared on the basis of an analysis of the literature and existing diagnostic protocols. Molecular testing is useful for diagnosis confirmation, as well as differential diagnosis, appropriate genetic counselling and access to clinical trials.

Ventricular septal defects (VSDs) are the commonest heart malformations and may affect the membranous or the muscular septum. Clinical presentation depends on the amount of interventricular flow, which is determined by the size of the defect and the relative resistances of the pulmonary and systemic vascular beds. The prevalence of VSD is estimated at about 5% among infants. Many small malformations present at birth may later undergo spontaneous closure. VSD may have autosomal dominant or autosomal recessive inheritance and may exist as isolated forms or as part of a syndrome. This Utility Gene Test was developed on the basis of an analysis of the literature and existing diagnostic protocols. It is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Stroke is defined as a focal or at times global neurological impairment of sudden onset and presumed vascular origin. 85% of strokes are due to cerebral ischemia and the other 15% to primary intracerebral hemorrhage. Ischemic stroke (IS) is characterized by complete or partial obstruction of a vessel in the brain, resulting in lack of blood supply and death of brain tissue. The most common causes of IS are atherosclerosis, cardioembolism and small-vessel disease (lacunar stroke). Genetic factors play important role. Incidence rates for IS in the 15- to 45-year age range are ≈10 per 100,000 person years. Hemorrhagic stroke (HS) is the least treatable and the most fatal form of cerebrovascular disease. Genetic mechanisms play a role in its development. Occurrence depends on many risk factors, including hypertension, heavy alcohol intake and anticoagulant treatment. According to the World Health Organization, 15 million people suffer stroke worldwide each year. The overall incidence of spontaneous HS worldwide is 24.6 per 100,000 person years. Strokes are the third most common cause of death and the most common cause of disability in developed countries. This Utility Gene Test was developed on the basis of an analysis of the literature and existing diagnostic protocols. It is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Cardiovascular disorders include various conditions characterized by morphological and functional defects of the heart and vascular system. Molecular biology techniques (in particular DNA sequencing) have recently offered new insights into the etiology of cardiovascular defects, revealing their association with germline as well as somatic mutations. Genetic tests are evaluated on the basis of their analytical and clinical validity, clinical utility, and ethical, legal and social implications. Next generation sequencing is so far the best approach for molecular diagnosis of congenital heart defects and vascular anomalies, the genetic and phenotypic heterogeneity of which makes them difficult to diagnose. Understanding the molecular causes of congenital heart defects and vascular anomalies has permitted clinical trials of drugs targeting affected genes and pathways. The articles in this Special Issue aim to provide guidance for those concerned with diagnosis and research in the field of cardiovascular defects. The approach to genetic testing is discussed.

Pulmonary stenosis (PS) is a congenital pulmonary valve malformation. It can be classified as valvular, subvalvular or supravalvular. Isolated forms of PS are rare. PS is associated with the development of massive pulmonary arterial dilatation. Patients with PS have a high consanguinity rate and the disorder is highly familial, which is why knowing the genetic aetiology of this defect is important. Prevalence is estimated at about 4/10,000 live births, and incidence at about 10% of all children with congenital heart defects. PS has prevalently autosomal dominant and rarely autosomal recessive inheritance. This Utility Gene Test was developed on the basis of an analysis of the literature and existing diagnostic protocols. It is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Cavernous cerebral malformations (CCM) are vascular malformations of the brain and spinal cord. CCM affect up to 0.5% of the general population, predisposing to headaches, seizures, cerebral hemorrhage and focal neurological deficit. CCM may be familial or sporadic. Familial forms have autosomal dominant inheritance. This Utility Gene Test was prepared on the basis of an analysis of the literature and existing diagnostic protocols. It is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Emberger Syndrome (ES) is a very rare genetic disorder associated with primary lymphedema, myelodysplasia and immunodeficiency. The syndrome has autosomal dominant inheritance with incomplete penetrance. Sporadic cases caused by de novo germinal mutations in the GATA2 gene have also been described. We developed the test protocol on the basis of the latest research findings and diagnostic protocols on lymphatic malformation in ES. The genetic test is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Aortic valve stenosis (AVS) is a congenital aortic defect in which the aortic lumen narrows due to thickening or calcification of the aortic valve without obstructing left ventricular outflow. Depending on the site of obstruction, AVS is classified as valvular, sub-valvular or supra-valvular. The prevalence of AVS is about 3% and increases with age. One in eight persons over the age of 75 years has moderate or severe AVS. AVS has autosomal dominant inheritance. It can be associated with mutations in the following genes: NOTCH1, SMAD6, SMAD4, and ELN. This Utility Gene Test was developed on the basis of the analysis of the literature and existing diagnostic protocols. It is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials, when available.

Marfan syndrome (MFS) is an inherited connective tissue disorder caused by heterozygous mutations in the FBN 1 gene. Clinical manifestations of MFS include aortic dilatation and dissection, as well as cardiac valvular, ocular, skeletal and neurological manifestations. Prevalence varies from 6 to 20 per 100,000 individuals. Revised Ghent Nosology (2010) is used to establish a clinically based suspected diagnosis to be confirmed by molecular testing. This Utility Gene Test was prepared on the basis of an analysis of the literature and existing diagnostic protocols. Molecular testing is useful for diagnosis confirmation, as well as differential diagnosis, appropriate genetic counselling and access to clinical trials.

We studied the scientific literature and disease guidelines to summarize the clinical utility of genetic testing for lymphedema distichiasis (LD) syndrome. LD is inherited in an autosomal dominant manner, and has unknown prevalence. It is caused by variations in the FOXC2 gene. Clinical diagnosis involves clinical examination, targeted at identifying primary lymphedema (chronic swelling of the extremities) and distichiasis (double row of eyelashes). The genetic test is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Coarctation of the aorta (CoA) is an inherited narrowing of the proximal descending thoracic aorta. Histological features include localized medial thickening and infolding with superimposed neointimal tissue. CoA is diagnosed by detection of a murmur or hypertension during routine examination. Typical clinical features are delayed or absent femoral pulses and difference in blood pressure between the arm and legs. These symptoms may appear in the first weeks of life or after the neonatal period. CoA accounts for 4-6% of all congenital heart defects and has a reported prevalence of about 4 per 10,000 live births. It is more common in males than females (59% vs 41%). This Utility Gene Test was developed on the basis of an analysis of the literature and existing diagnostic protocols. It is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Variants affecting the function of genes in the RAS–mitogen-activated protein kinase (MAPK) signal transduction pathway have been identified as responsible for a group of developmental syndromes known as RASopathies. Noonan (NS) and cardiofaciocutaneous syndromes (CFC) represent the most frequent and best characterized RASopathies. Many cases of RASopathies are associated with lymphatic malformations that finally may result in lymphedema. We developed the test protocol “Lymphedema in RASopathies” on the basis of the latest research findings and diagnostic protocols on lymphatic malformation in RASopathies. The genetic test is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Ebstein anomaly (EA) is a rare congenital tricuspid valve malformation, characterized by downward displacement of the septal leaflet and an atrialized right ventricle. About 80% of cases of EA are non-syndromic; in the other 20%, the anomaly is associated with a chromosomal or Mendelian syndrome. The prevalence of EA is estimated at about 1 per 20,000 live births, and accounts for less than 1% of all congenital heart defects. EA has autosomal dominant inheritance. Likely causative genes are: NKX2-5, MYH7 and TPM1. This Utility Gene Test was developed on the basis of an analysis of the literature and existing diagnostic protocols. It is useful for confirming diagnosis, as well as for differential diagnosis, potential risk assessment and access to clinical trials.

Atrioventricular septal defect (AVSD) is a congenital heart defect characterized by a shared atrioventricular junction coexisting with deficient atrioventricular septation. The main morphological characteristic of AVSD is a common atrioventricular canal. The prevalence of AVSD is estimated at 0.31/1000 live births and is higher among subjects with PTPN11 mutations. ASD may have autosomal dominant or autosomal recessive inheritance. This Utility Gene Test was prepared on the basis of an analysis of the literature and existing diagnostic protocols. It is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Hennekam Syndrome (HS) is a combination of congenital lymphatic malformation, lymphangiectasia and other disorders. It is a very rare disorder with autosomal recessive inheritance. We developed the test protocol “Hennekam Syndrome” on the basis of the latest research findings and diagnostic protocols on lymphatic malformation in HS. The genetic test is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Tetralogy of Fallot (ToF) combines congenital cardiac defects including ventricular septal defect, pulmonary stenosis, an overriding aorta and right ventricular hypertrophy. Clinical manifestation of this defect depends on the direction and volume of shunting of blood through the ventricular septal defect and the associated right ventricular and pulmonary artery pressures. ToF accounts for 3-5% of congenital heart defects or 0.28 cases every 1000 live births. ToF has autosomal dominant inheritance. This Utility Gene Test was developed on the basis of an analysis of the literature and existing diagnostic protocols. It is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Atrial septal defect (ASD) is a congenital heart defect characterized by an opening in the atrial septum. About 1/3 of patients with Noonan syndrome caused by mutation in the PTPN11 gene have ASD. The prevalence of ASD is estimated at 100 per 100,000 live births. ASD may have autosomal dominant or recessive inheritance. This Utility Gene Test was prepared on the basis of an analysis of the literature and existing diagnostic protocols. It is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Guanylate Cyclase-Activating Protein 1 (GCAP1) regulates the enzymatic activity of the photoreceptor guanylate cyclases (GC), leading to inhibition or activation of the cyclic guanosine monophosphate (cGMP) synthesis depending on its Ca2+- or Mg2+-loaded state. By genetically screening a family of patients diagnosed with cone-rod dystrophy, we identified a novel missense mutation with autosomal dominant inheritance pattern (c.332A>T; p.(Glu111Val); E111V from now on) in the GUCA1A gene coding for GCAP1. We performed a thorough biochemical and biophysical investigation of wild type (WT) and E111V human GCAP1 by heterologous expression and purification of the recombinant proteins. The E111V substitution disrupts the coordination of the Ca2+ ion in the high-affinity site (EF-hand 3, EF3), thus significantly decreasing the ability of GCAP1 to sense Ca2+ (∼80-fold higher Kdapp compared to WT). Both WT and E111V GCAP1 form dimers independently on the presence of cations, but the E111V Mg2+-bound form is prone to severe aggregation over time. Molecular dynamics simulations suggest a significantly increased flexibility of both the EF3 and EF4 cation binding loops for the Ca2+-bound form of E111V GCAP1, in line with the decreased affinity for Ca2+. In contrast, a more rigid backbone conformation is observed in the Mg2+-bound state compared to the WT, which results in higher thermal stability. Functional assays confirm that E111V GCAP1 interacts with the target GC with a similar apparent affinity (EC50); however, the mutant shifts the GC inhibition out of the physiological [Ca2+] (IC50E111V ∼10 μM), thereby leading to the aberrant constitutive synthesis of cGMP under conditions of dark-adapted photoreceptors.

Vascular anomalies (VAs) have phenotypic variability within the same entity, overlapping clinical features between different conditions, allelic and locus heterogeneity and the same disorder can be inherited in different ways. Most VAs are sporadic (paradominant inheritance or de novo somatic or germline mutations), but hereditary forms (autosomal dominant or recessive) have been described. This Utility Gene Test was developed on the basis of an analysis of the literature and existing diagnostic protocols. The genetic test is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant vascular dysplasia characterized by telangiectases and arteriovenous malformations. These lesions cause bleeding, particularly in the nose, gastrointestinal tract and brain. HHT has incomplete penetrance, variable expressivity and genetic heterogeneity. De novo mutations associated with the onset of sporadic HHT have been reported. This Utility Gene Test was prepared on the basis of an analysis of the literature and existing diagnostic protocols. It is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

In this study, we assessed the prevalence of polymorphisms in genes involved in hyperhomocysteinemia or hemostasis to shed light on their role, if any, in retinal vein occlusion (RVO). We recruited 37 Italian patients (17 men and 20 women) with a diagnosis of central or branch RVO based on fundus examination and retinal fluorescein angiography, as well as 45 healthy controls. Risk factors and family history of RVO of all subjects were recorded. The distributions of polymorphisms in patients and controls were evaluated using the χ(2) test and OR. We confirmed an increased risk in subjects with dyslipidemia (high density lipoprotein59 mg/dL: 17.8% of controls, 43.2% of patients, P = 0.0002; low density lipoprotein130 mg/dL: 26.7% controls, 54.1% patients, P = 0.0002), arterial hypertension (60% controls, 75.7% patients, P = 0.023), and high body mass index (28.9% controls, 70.3% patients, P0.0001, and excluded involvement of the selected polymorphisms in RVO. Overall, the tested polymorphisms did not appear to be useful for assessing predisposition or for the diagnosis and prognosis of RVO.

Hepatitis B virus (HBV) is the infectious agent of both acute and chronic hepatitis. HBV exists in multiple genotypic variants that differ in their capacity to become persistent chronic infections and in their clinical manifestations, including hepatocellular carcinoma. The 8 genotypes (A-H) of HBV show a specific worldwide geographic distribution and are correlated with different disease course, severity, and response to therapy. We isolated DNA from 75 HBV-positive blood donors, chosen randomly from the database of the National Blood Bank in Tirana, to specifically analyze the UGT1A1 polymorphism to determine its correlations with bilirubin levels and liver function. The large number of subjects who were HBV-positive carriers of heterozygosis or homozygosis for the UGT1A1*28 (TA)7 polymorphism suggests that these individuals may be more susceptible to cancer and should follow a strict regime of prevention.

The aim of this study was to assess the association between the TNFR1 rs2234649 polymorphism and ankylosing spondylitis susceptibility in a Russian Caucasian population. A total of 41 ankylosing spondylitis patients and 43 healthy controls, matched according to age and sex, were enrolled, and polymerase chain reaction-restriction fragment length polymorphism analysis was used to genotype the rs2234649 variant. We evaluated genotype distributions in the patient and control groups with the chi-square test, and assessed the relationship between genotypes and ankylosing spondylitis using the odds ratio. Our analysis showed that the rs2234649 polymorphism does not increase ankylosing spondylitis risk. In conclusion, the TNFR1 gene polymorphism tested does not appear to be useful for assessing predisposition to this disease or for its diagnosis or prognosis.

A targeted next generation sequencing (NGS) approach analysing contemporaneously 20 different genes mainly involved in craniosynostosis was adopted to molecularly diagnose the family of a 2-years old girl affected by Saethre–Chotzen syndrome, a syndromic form of craniosynostosis. The identified pathogenic variant in the TWIST1 gene lies in a conserved residue (Arg118) that shifts from a positively charged amino acid to a non-polar amino acid and segregates in all the examined affected familial members, although with variable phenotypic expression. An accurate molecular diagnosis is of obvious value for the clinical management of individuals with isolated or syndromic craniosynostosis to define their medical needs, the recurrence risk and allow the identification of available therapeutic opportunity. Given the high number of associated genes, an NGS approach is the election choice to increase the yield of genetic diagnosis, leading to an expansion of the genotypic and phenotypic spectrum of these rare syndromes

WNK1 (With No-lysine Kinase 1), a serine-threonine kinase, regulates blood pressure by acting on various sodium transport-related ion channels. Several studies report a link between common variants of the WNK1 gene and hypertension. No data exists on Russian populations. Our aim was to evaluate the association between the WNK1 AluYb8 polymorphism and hypertension susceptibility in a Russian Caucasian population. A total of 66 patients with arterial hypertension and 40 controls were screened by polymerase chain reaction. We evaluated the genotype distribution in the patient and control groups using a chi-square test and assessed the relationship between genotypes and hypertension. This preliminary study on a small number of individuals suggests the absence of any association between the AluYb8 polymorphism and increased blood pressure. The polymorphism therefore does not increase the risk of hypertension, and in our cohort, is not a major contributor to blood pressure variability. It is therefore not useful for evaluating predisposition to hypertension, at least in the Krasnoyarsk region

Purpose: Familial adenomatous polyposis is an inherited precancerous condition characterized by multiple colorectal polyps. This brief report describes three generations of a family with a history of colorectal cancer in which genetic testing was useful for detecting individuals at risk. Methods: A next generation sequencing custom gene panel comprising 11 genes associated with familial adenomatous polyposis and colorectal cancer was used to screen the proband. Sanger sequencing was used for family segregation study. Results: Genetic testing showed that the proband, her affected sister and asymptomatic son carried the p.(Gln1338*) variant in the APC gene. Conclusion: APC genetic variations are the most frequent cause of familial adenomatous polyposis and are inherited with autosomal dominant transmission. According to the literature, the variation found in this family is associated with the condition and lies in a known mutation cluster region. Pedigree analysis suggested that the proband’s son should be included in a regular surveillance program to monitor for development of the disease and avoid more serious consequences. To our knowledge, this is the first clinical and genetic report of the condition described in an Albanian family.

The aim of this review is to describe a series of ten genetic diseases with Mendelian inheritance pattern in people of low- or middle-income countries, which can be easily identified with simple and affordable methods. Recent information shows that although genetic diseases account for more than 10% of infant mortality in such countries, testing, counseling, and treatment of genetic diseases is not a priority. The selection criteria for the genetic tests that are discussed in this review are: i) the frequency of the genetic disease in the general population, ii) the cost and ease of execution, and iii) the report of validated methods in the literature for the diagnosis of these diseases. The goal is to promote diagnosis of genetic diseases at low-cost and with relative ease, thereby enabling appropriate treatments, reducing mortality, and preventing genetic diseases in high-risk families.

Chronic fatigue syndrome (CFS) is a disease that can seriously impair one's quality of life; patients complain of excessive fatigue and myalgia following physical exertion. This disease may be associated with abnormalities in genes affecting exercise tolerance and physical performance. Adenosine monophosphate deaminase (AMPD1), carnitine palmitoyltransferase II (CPT2), and the muscle isoform of glycogen phosphorylase (PYGM) genes provide instructions for producing enzymes that play major roles in energy production during work. The aim of this study was to look for evidence of genotype-associated excessive muscle fatigue. Three metabolic genes (AMPD1, CPT2, and PYGM) were therefore fully sequenced in 17 Italian patients with CFS. We examined polymorphisms known to alter the function of these metabolic genes, and compared their genotypic distributions in CFS patients and 50 healthy controls using chi-square tests and odds ratios. One-way analysis of variance with F-ratio was carried out to determine the associations between genotypes and disease severity using CF scores. No major genetic variations between patients and controls were found in the three genes studied, and we did not find any association between these genes and CFS. In conclusion, variations in AMPD1, CPT2, and PGYM genes are not associated with the onset, susceptibility, or severity of CFS.

Polymorphisms in the glucocorticoid receptor (GR) gene have been associated with altered sensitivity to glucocorticoids. We designed a high-resolution melting (HRM) assay to detect, simultaneously, the three most intriguing GR polymorphisms, selected on the bases of clinical relevance and frequencies in caucasian population as described in literature. HRM enables the detection of ER22/23EK and N363S genotypes but fails to discriminate homozygous mutant for the BclI polymorphism from wild-type samples, however a simple spike experiment leads to a clear discrimination between these genotypes. The analyses were performed on a cohort of 70 healthy Caucasian subjects. The method was validated by restriction fragment length polymorphisms; HRM results were found to be in 100% concordance with those observed with the restriction enzymes. We also employed this method on a population of 40 Crohn Disease patients; the analysis demonstrated a significantly higher frequency of the BclI polymorphism in patients than in healthy volunteers. This is, at now, the less expensive and time-and work-saving method to detect GR mutations, providing precision, fast screening and high throughput capabilities.