Társis Paiva Vieira

OCT4 immunohistochemistry may be necessary to identify the real risk of gonadal tumors in patients with Turner syndrome and Y chromosome sequences

BACKGROUND The aim of this study was to investigate the frequency of gonadal tumors among patients with Turner syndrome (TS) carrying Y-derivative sequences in their chromosomal constitution. METHODS Six out of 260 patients with TS were selected based on mosaicism of the entire Y chromosome; 10 were included because Y-derivative sequences have been detected by PCR with specific oligonucleotides (sex-determining region on the Y, testis specific-protein, Y and DYZ3) and further confirmed by FISH. The 16 patients were subjected to bilateral gonadectomy at ages varying from 8.7 to 18.2 years. Both histopathological investigation with hematoxylin and eosin (H&E) and immunohistochemical analysis with anti-octamer-binding transcription factor 4 (OCT4) antibody were performed. RESULTS Gonadal neoplasia was not detected in any of the 32 gonads evaluated by H&E; however, four gonads (12%) from three patients (19%) had positive OCT4 staining in 50-80% of nuclei, suggesting the existence of germ cell tumors (gonadoblastoma or in situ carcinoma). CONCLUSIONS Evaluation of the real risk of development of gonadal tumors in TS patients with Y-derivative sequences in their chromosomal constitution may require a specific histopathological study, such as immunohistochemistry with OCT4.

Atypical copy number abnormalities in 22q11.2 region: report of three cases.

The 22q11.2 Deletion Syndrome (22q11.2DS) is the most common microdeletion syndrome in humans, with a highly variable phenotype. This chromosomal region contains low copy repeat (LCR) sequences that mediate non-allelic homologous recombination which predispose to copy number abnormalities at this locus. This article describes three patients investigated for suspicion of 22q11.2DS presenting atypical copy number abnormalities overlapping or not with the common ∼3 Mb deletion. They were investigated by G-banding karyotype, Multiplex-ligation dependent probe amplification (MLPA) and array Genomic Hibridization (aGH). Clinical and molecular data were compared with literature, in order to contribute to genotype-phenotype correlation. Atypical chromosomal abnormalities were detected: 3.6 Mb deletion at 22q11.21-q11.23 between LCRs B-F in patient 1 and approximately 1.5 Mb deletion at 22q11.21-q11.22 between LCRs D-E in patients 2 and 3. The breakpoints detected in patient 1 have not been previously described. These findings exemplify the complexity and genetic heterogeneity observed in 22q11.2 region and corroborates the idea that genetic modifiers contribute to the phenotypic variability observed in proximal and distal 22q11.2 deletion syndromes.

Insertional Translocation of 15q25-q26 into 11p13 and Duplication at 8p23.1 Characterized by High Resolution Arrays in a Boy With Congenital Malformations and Aniridia

We report on a boy presenting submucous cleft palate, hydronephrosis, ventriculoseptal defect, aniridia, and developmental delay. Additional material on 11p13 was cytogenetically visible and array analyses identified a duplicated segment on 15q25‐26 chromosome region; further, array analyses revealed a small deletion (49 kb) at 11p13 region involving the ELP4 gene and a duplication at 8p23.1. Results were confirmed with both molecular and molecular cytogenetics techniques. Possibilities for etiological basis of clinical phenotype are discussed.

Maternally Inherited Partial Monosomy 9p (pter ! p24.1) and Partial Trisomy 20p (pter ! p12.1) Characterized by Microarray Comparative Genomic Hybridization

We report on a 17‐year‐old patient with midline defects, ocular hypertelorism, neuropsychomotor development delay, neonatal macrosomy, and dental anomalies. DNA copy number investigations using a Whole Genome TilePath array consisting, of 30K BAC/PAC clones showed a 6.36 Mb deletion in the 9p24.1–p24.3 region and a 14.83 Mb duplication in the 20p12.1–p13 region, which derived from a maternal balanced t(9;20)(p24.1;p12.1) as shown by FISH studies. Monosomy 9p is a well‐delineated chromosomal syndrome with characteristic clinical features, while chromosome 20p duplication is a rare genetic condition. Only a handful of cases of monosomy 9/trisomy 20 have been previously described. In this report, we compare the phenotype of our patient with those already reported in the literature, and discuss the role of DMRT, DOCK8, FOXD4, VLDLR, RSPO4, AVP, RASSF2, PROKR2, BMP2, MKKS, and JAG1, all genes mapping to the deleted and duplicated regions.

Clinical, cytogenetic, and molecular characterization of six patients with ring chromosomes 22, including one with concomitant 22q11.2 deletion

We report here on six patients with a ring chromosome 22 and the range of cytogenetic and phenotypic features presented by them. Genomic analysis was carried out using classical and molecular cytogenetics, MLPA (Multiplex Ligation‐dependent Probe Amplification) and genome‐wide SNP‐array analysis. The ring was found in all patients, but Patient 6 displayed constitutional mosaicism with a normal cell line. Five patients had deletions in the ring chromosome 22, and in four of them the breakpoints—unique for each patient—could be identified by genome‐wide SNP‐array analysis. One patient presented with a 22q11.2 deletion concomitant with the deletion caused by the ring formation. Common phenotypic features included autism, speech delay and seizures, as previously reported for individuals with r(22) and/or 22q13.3 deletions. Investigation of the genes within the deletions revealed multiple genes related to development of the central nervous system, psychomotor delay, severe language impairment, hypotonia, and autistic symptoms. There was no clear correlation between the severity of clinical features and the size of the deleted segment. This study underscores the variability in ring structure and clinical presentation of the r(22) and adds information to the limited literature on this rare disorder.

Local Strategies to Address Health Needs of Individuals With Orofacial Clefts in Alagoas, Brazil

Objective To describe demographic and clinical-genetic characteristics of patients from a poor area of Brazil and to share experience on how the local genetic unit has addressed their major health needs. Design Descriptive cohort. Setting A clinical-genetic unit, a cytogenetics unit, and a regional cleft team located in the northeast and southeast of Brazil. Participants A total of 133 individuals with orofacial clefts who attended the surgical call of a nongovernmental organization. From this group, 125, 77, and 13 patients completed phases 1, 2, and 3, respectively. Methods Phase 1 comprised a description of demographic characteristics recorded through interviews. Phase 2 included a clinical-genetic evaluation using a pretested form, as well as cytogenetic analyses of selected patients. Phase 3 comprised collaborative action to address major health needs of patients without primary surgery. The Fisher test was used for statistics with p value < .05. Results A majority of patients were rural residents with isolated cleft lip with cleft palate. Ages ranged between 0 and 30 years. Fifty percent had never undergone surgery; whereas, 100% had never attended a genetic evaluation. Isolated cleft was diagnosed in 77.9%, syndromes in 14.3%, and multiple congenital abnormalities in 7.8%. Positive familial history of clefts occurred in 28%; whereas, parental consanguinity was present in 7.8% cases. A total of 23 individuals without cleft surgery were registered for multidisciplinary treatment. Conclusions Findings revealed high levels of unmet medical needs and provided an evidence base for health care planning. Collaborative action was crucial and might be applied to other regions in Brazil.

A familial case with interstitial 2q36 deletion: Variable phenotypic expression in full and mosaic state

Submicroscopic chromosomal anomalies play an important role in the etiology of craniofacial malformations, including midline facial defects with hypertelorism (MFDH). MFDH is a common feature combination in several conditions, of which Frontonasal Dysplasia is the most frequently encountered manifestation; in most cases the etiology remains unknown. We identified a parent to child transmission of a 6.2 Mb interstitial deletion of chromosome region 2q36.1q36.3 by array-CGH and confirmed by FISH and microsatellite analysis. The patient and her mother both presented an MFDH phenotype although the phenotype in the mother was much milder than her daughter. Inspection of haplotype segregation within the family of 2q36.1 region suggests that the deletion arose on a chromosome derived from the maternal grandfather. Evidences based on FISH, microsatellite and array-CGH analysis point to a high frequency mosaicism for presence of a deleted region 2q36 occurring in blood of the mother. The frequency of mosaicism in other tissues could not be determined. We here suggest that the milder phenotype observed in the probands mother can be explained by the mosaic state of the deletion. This most likely arose by an early embryonic deletion in the maternal embryo resulting in both gonadal and somatic mosaicism of two cell lines, with and without the deleted chromosome. The occurrence of gonadal mosaicism increases the recurrence risk significantly and is often either underestimated or not even taken into account in genetic counseling where new mutation is suspected.

Genomic imbalances in syndromic congenital heart disease

OBJECTIVE To identify pathogenic genomic imbalances in patients presenting congenital heart disease (CHD) with extra cardiac anomalies and exclusion of 22q11.2 deletion syndrome (22q11.2 DS). METHODS 78 patients negative for the 22q11.2 deletion, previously screened by fluorescence in situ hybridization (FISH) and/or multiplex ligation probe amplification (MLPA) were tested by chromosomal microarray analysis (CMA). RESULTS Clinically significant copy number variations (CNVs ≥300kb) were identified in 10% (8/78) of cases. In addition, potentially relevant CNVs were detected in two cases (993kb duplication in 15q21.1 and 706kb duplication in 2p22.3). Genes inside the CNV regions found in this study, such as IRX4, BMPR1A, SORBS2, ID2, ROCK2, E2F6, GATA4, SOX7, SEMAD6D, FBN1, and LTPB1 are known to participate in cardiac development and could be candidate genes for CHD. CONCLUSION These data showed that patients presenting CHD with extra cardiac anomalies and exclusion of 22q11.2 DS should be investigated by CMA. The present study emphasizes the possible role of CNVs in CHD.

Partial monosomy 21 (q11.2→q21.3) combined with 3p25.3→pter monosomy due to an unbalanced translocation in a patient presenting dysmorphic features and developmental delay

We describe a female patient of 1 year and 5 months-old, referred for genetic evaluation due to neuropsychomotor delay, hearing impairment and dysmorphic features. The patient presents a partial chromosome 21 monosomy (q11.2→q21.3) in combination with a chromosome 3p terminal monosomy (p25.3→pter) due to an unbalanced de novo translocation. The translocation was confirmed by fluorescence in situ hybridization (FISH) and the breakpoints were mapped with high resolution array. After the combined analyses with these techniques the final karyotype was defined as 45,XX,der(3)t(3;21)(p25.3;q21.3)dn,-21.ish der(3)t(3;21)(RP11-329A2-,RP11-439F4-,RP11-95E11-,CTB-63H24+).arr 3p26.3p25.3(35,333-10,888,738))×1,21q11.2q21.3(13,354,643-27,357,765)×1. Analysis of microsatellite DNA markers pointed to a paternal origin for the chromosome rearrangement. This is the first case described with a partial proximal monosomy 21 combined with a 3p terminal monosomy due to a de novo unbalanced translocation.

Anthropometric and body-mass composition suggests an intrinsic feature in Williams-Beuren syndrome

OBJECTIVE Although considered a well-known condition, there is only one study describing the body composition among individuals with Williams-Beuren syndrome. The aim was to characterize the nutritional status in Brazilian individuals with this condition. METHODS Cross-sectional study was designed to evaluate clinical and nutritional data of 17 Brazilian patients. Z-scores for height, weight, body mass index, triceps and subscapular skinfold thickness, arm circumference, arm muscle area, arm fat area were calculated. Wilcoxons test was used to investigate differences between the z-scores of the anthropometrical measures and zero. RESULTS Four children were considered stunted and two severely malnourished. The z-score mean value for height was -1.14 ± 1.00 (p-value = 0.004), for weight, -0.67 ± 1.19 (p-value = 0.0443), for arm circumference, -0.94 ± 1.14 (p-value = 0.0222), for triceps skinfold thickness, -0.59 ± 0.63 (p-value = 0.0042) and for arm fat area -0.67 ± 0.67 (p-value = 0.0061). CONCLUSION Short stature seen in this series confirms a previous study describing this feature in a German population, which would suggest it as an intrinsic feature in Williams-Beuren syndrome. In addition, skinfold thickness measures have not been previously performed in this syndrome and detected abnormalities in fat stores in this sample. Considering this method a fast and low-cost way to evaluate body composition, similar studies could be performed in other populations in order to better characterize this issue. Morbidity related with this genetics condition and information for clinical investigation and clinical follow-up are also discussed.