Paula Frassinetti Vasconcelos de Medeiros

Using a combination of MLPA kits to detect chromosomal imbalances in patients with multiple congenital anomalies and mental retardation is a valuable choice for developing countries.

Conventional karyotyping detects anomalies in 3-15% of patients with multiple congenital anomalies and mental retardation (MCA/MR). Whole-genome array screening (WGAS) has been consistently suggested as the first choice diagnostic test for this group of patients, but it is very costly for large-scale use in developing countries. We evaluated the use of a combination of Multiplex Ligation-dependent Probe Amplification (MLPA) kits to increase the detection rate of chromosomal abnormalities in MCA/MR patients. We screened 261 MCA/MR patients with two subtelomeric and one microdeletion kits. This would theoretically detect up to 70% of all submicroscopic abnormalities. Additionally we scored the de Vries score for 209 patients in an effort to find a suitable cut-off for MLPA screening. Our results reveal that chromosomal abnormalities were present in 87 (33.3%) patients, but only 57 (21.8%) were considered causative. Karyotyping detected 15 abnormalities (6.9%), while MLPA identified 54 (20.7%). Our combined MLPA screening raised the total detection number of pathogenic imbalances more than three times when compared to conventional karyotyping. We also show that using the de Vries score as a cut-off for this screening would only be suitable under financial restrictions. A decision analytic model was constructed with three possible strategies: karyotype, karyotype + MLPA and karyotype + WGAS. Karyotype + MLPA strategy detected anomalies in 19.8% of cases which account for 76.45% of the expected yield for karyotype + WGAS. Incremental Cost Effectiveness Ratio (ICER) of MLPA is three times lower than that of WGAS, which means that, for the same costs, we have three additional diagnoses with MLPA but only one with WGAS. We list all causative alterations found, including rare findings, such as reciprocal duplications of regions deleted in Sotos and Williams-Beuren syndromes. We also describe imbalances that were considered polymorphisms or rare variants, such as the new SNP that confounded the analysis of the 22q13.3 deletion syndrome.

The phenotypic spectrum of congenital Zika syndrome

In October 2015, Zika virus (ZIKV) outbreak the Brazilian Ministry of Health (MoH). In response, the Brazilian Society of Medical Genetics established a task force (SBGM‐ZETF) to study the phenotype of infants born with microcephaly due to ZIKV congenital infection and delineate the phenotypic spectrum of this newly recognized teratogen. This study was based on the clinical evaluation and neuroimaging of 83 infants born during the period from July, 2015 to March, 2016 and registered by the SBGM‐ZETF. All 83 infants had significant findings on neuroimaging consistent with ZIKV congenital infection and 12 had confirmed ZIKV IgM in CSF. A recognizable phenotype of microcephaly, anomalies of the shape of skull and redundancy of the scalp consistent with the Fetal Brain Disruption Sequence (FBDS) was present in 70% of infants, but was most often subtle. In addition, features consistent with fetal immobility, ranging from dimples (30.1%), distal hand/finger contractures (20.5%), and feet malpositions (15.7%), to generalized arthrogryposis (9.6%), were present in these infants. Some cases had milder microcephaly or even a normal head circumference (HC), and other less distinctive findings. The detailed observation of the dysmorphic and neurologic features in these infants provides insight into the mechanisms and timings of the brain disruption and the sequence of developmental anomalies that may occur after prenatal infection by the ZIKV.

ATXN3, ATXN7, CACNA1A, and RAI1 Genes and Mitochondrial Polymorphism A10398G Did Not Modify Age at Onset in Spinocerebellar Ataxia Type 2 Patients from South America

Fernanda S. Pereira & Thais L. Monte & Lucas D. Locks-Coelho & Amanda S. P. Silva & Orlando Barsottini & Jose L. Pedroso & Mario Cornejo-Olivas & Pilar Mazzetti & Clecio Godeiro & Fernando R. Vargas & Maria-Angelica F. D. Lima & Helio van der Linden Jr & Maria Betânia Pereira Toralles & Paula F. V. Medeiros & Erlane Ribeiro & Pedro Braga-Neto & Diego Salarini & Raphael M. Castilhos & Maria-Luiza Saraiva-Pereira & Laura Bannach Jardim & Rede Neurogenetica

Patients With Mucopolysaccharidosis Have Tendencies Towards Vertical Facial Growth

PURPOSE Studies addressing the changes in craniofacial morphology of patients with mucopolysaccharidosis (MPS) are important for a better understanding of the progression of this disease. The present objective was to identify major cephalometric abnormalities in these patients. MATERIALS AND METHODS This was a cross-sectional case-and-control study. The sample was composed of 2 types of study subjects (patients with MPS and normal subjects). The outcome variables were numerous cephalometric elements that measure facial height, dental positioning, facial growth pattern, and mandibular and maxillary positioning. The Student t test was used to compare the mean angular and linear measurements of the case and control groups and the level of significance was set at a P value less than .05. The Bonferroni method was used for adjustment of the P value (P<.003 was deemed significant). RESULTS The control group consisted of randomly selected subjects matched to the patients with MPS for the demographic variables of gender and age. Seventeen patients with MPS were evaluated (64.7% female). The mean age of the sample was 13.29 years. One patient had MPS I, 8 had MPS IV, and 8 had MPS VI. The results showed important differences between groups in angular measurements (angle formed by the line between the sella and nasion [SN] and the plane of the gonion and gnathion, angle formed by the intersection of the gnathion point and the SN line, angle formed by the intersection of the long axis of the lower incisor with the line between the nasion and the B point, angle formed by the intersection of the long axes of the upper and lower incisors, and angle formed by the Frankfort horizontal plane with the mandibular plane) and linear measurements (condyle to A point, condyle to gnathion, pro-nasal ( Pn) point to the line between the pogonion and upper incisor, and the nearest point of the anterior half of the soft palate to the posterior pharyngeal wall). The angle formed by the SN line with the plane between the gonion and the gnathion and the distance from the condyle to the A point showed meaningful differences after Bonferroni adjustment. CONCLUSION Patients with MPS present a tendency toward vertical growth that results in a dolichocephalic facial pattern. In addition, a smaller nasopharyngeal space was observed, a factor that might be responsible for the mouth breathing observed in these patients.

Major Contribution of Genomic Copy Number Variation in Syndromic Congenital Heart Disease: The Use of MLPA as the First Genetic Test

Congenital heart disease (CHD) is the most common congenital disorder among live births. When associated with extracardiac abnormalities, it is characterized as a syndromic heart disease (syndromic CHD) and corresponds to 25% of all liveborn infants with a heart defect. The etiology in about 65% of the cases still remains unknown, and in about 35% of the patients, it is associated with genetic factors. In the present study, MLPA and SNP-array techniques were used to investigate a group of 47 patients with syndromic CHD. In total, 16 defects (34%) were identified, of which 12 (25.5%) were classified as pathogenic or probably pathogenic. The most frequent abnormalities were 22q11.2 deletion (22q11.2 deletion syndrome) and 7q11.23 deletion (Williams-Beuren syndrome). We also show that rarer malformations may be associated with syndromic CHD, such as 14q32.33 deletion as well as 17q25.3, 15q11.2 (BP1-BP2), 22q13.31, and 12p13.31 (SLC2A3) duplications. The present study demonstrates that CNVs are important causal factors and should be studied in patients with syndromic CHD. Furthermore, the use of MLPA as a first screening test was appropriate, as this less expensive technology detected 11 of the 12 pathogenic abnormalities (91.6%).

Evaluation of plasma biomarkers of inflammation in patients with maple syrup urine disease

Maple syrup urine disease (MSUD) is an autosomal recessive inherited disorder that affects branched-chain amino acid (BCAA) catabolism and is associated with acute and chronic brain dysfunction. Recent studies have shown that inflammation may be involved in the neuropathology of MSUD. However, these studies have mainly focused on single or small subsets of proteins or molecules. Here we performed a case-control study, including 12 treated-MSUD patients, in order to investigate the plasmatic biomarkers of inflammation, to help to establish a possible relationship between these biomarkers and the disease. Our results showed that MSUD patients in treatment with restricted protein diets have high levels of pro-inflammatory cytokines [IFN-γ, TNF-α, IL-1β and IL-6] and cell adhesion molecules [sICAM-1 and sVCAM-1] compared to the control group. However, no significant alterations were found in the levels of IL-2, IL-4, IL-5, IL-7, IL-8, and IL-10 between healthy controls and MSUD patients. Moreover, we found a positive correlation between number of metabolic crisis and IL-1β levels and sICAM-1 in MSUD patients. In conclusion, our findings in plasma of patients with MSUD suggest that inflammation may play an important role in the pathogenesis of MSUD, although this process is not directly associated with BCAA blood levels. Overall, data reported here are consistent with the working hypothesis that inflammation may be involved in the pathophysiological mechanism underlying the brain damage observed in MSUD patients.

Correction: Biotinidase deficiency: Genotype-biochemical phenotype association in Brazilian patients

[This corrects the article DOI: 10.1371/journal.pone.0177503.].

Contents Vol. 7, 2016

Geert Mortier Department of Medical Genetics Antwerp University Hospital Prins Boudewijnlaan 43 B–2650 Antwerp (Belgium) Tel. +32 3 275 9773 (secretary) Tel. +32 3 275 9766 (direct) Fax +32 3 275 9723 E-mail: geert.mortier@ua.ac.be Cynthia C. Morton Harvard Medical School Brigham and Women’s Hospital New Research Building, Room 160D 77 Avenue Louis Pasteur Boston, MA 02115 (USA) Tel. +1 617 525 4535 Fax +1 617 525 4533 E-mail c.morton@partners.org

Identifying CNVs in 15q11q13 and 16p11.2 of Patients with Seizures Increases the Rates of Detecting Pathogenic Changes

Chromosomal changes are frequently observed in patients with syndromic seizures. Understanding the genetic etiology of this pathology is crucial for the guidance and genetic counseling of families as well as for the establishment of appropriate treatment. A combination of MLPA kits was used to identify pathogenic CNVs in a group of 70 syndromic patients with seizures. Initially, a screening was performed for subtelomeric changes (MLPA P036 and P070 kits) and for the regions most frequently related to microdeletion/microduplication syndromes (MLPA P064). Subsequently, the MLPA P343 was used to identify alterations in the 15q11q13, 16p11.2, and 22q13 regions. Screening with MLPA P343 allowed a 10-15.7% increase in the detection rate of CNVs reinforcing the importance of investigating changes in 15q11q13 and 16p11.2 in syndromic patients with seizures. We also demonstrated that the MLPA technique is an alternative with a great diagnostic potential, and we proposed its use as part of the initial assessment of syndromic patients with seizures.

Abstract 1837: Clinical diversity and tumor spectrum in Xeroderma Pigmentosum Brazilian patients

Xeroderma Pigmentosum (XP) is a rare autossomic recessive hereditary disorder in which normal ability to repair DNA damage caused by ultraviolet light (UV) is deficient due to the presence of mutations in nucleotide excision repair pathway genes (XPA, ERCC3, XPC, ERCC2, DDB, ERCC4 and ERCC5) or in POLH gene, responsible for the replication of damaged DNA on the leading strand. These different genetic alteration result in distict phenotypes classifified into eight genetic complementation sub groups, XP-A to XP-G and a variant group XP-V. Clinical characteristics of the syndrome include skin poikiloderma and eye hypersensibility to UV radiation. Carriers have an increased risk of early onset multiple cutaneous, mucocutaneous and ophthalmologic malignancies when compared with normal population. Occasionally neurological impairment is observed in certain variations of the syndrome. Given the paucity of specific literature data about the incidence and clinical profile of the disease in Brazilian population, this study was conducted to describe clinical diversity and tumor spectrum of XP syndrome in Brazilian population. Twenty-nine XP patients from 19 non-related families from Hospital A.C. Camargo (Sao Paulo, Brazil), Hospital Universitario Alcides Carneiro (Campina Grande, Paraiba) and Hospital de Clinicas de Porto Alegre (Rio Grande do Sul, Brazil). Data collection was performed after genetic counseling and signed informed consent. Clinical characteristics were obtained through medical ascertainment. The median age was 24 (4 to 61 years) in a predominant female population (19/29). Basal cell carcinomas (BCC) were the most frequent neoplasm, present in 86,20% (25/29) of all patients, with the occurrence of up to 60 BCCs in a same patient. Squamous cell carcinomas and melanoma were present in 66,7% and 37,5% respectively. Six patients developed the first malignant tumor before the age of six and four patients developed the first tumor in early adulthood. One male patient developed a diffuse gastric cancer at 50 years old. Visual impairment occurred in 45,83% of the patient. Despite the unknown frequency of affected patients, the Brazilian population of XP cases seems to be underestimated. Genetic counseling is fundamental to provide information to carriers and family members and enable preventive measurements. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1837. doi:10.1158/1538-7445.AM2011-1837