Cytogenetic and molecular characterization of an SRY-negative 46, XX ovotesticular DSD: a case report / Caracterização citogenética e molecular de um DDS ovotesticular 46, XX SRY-negativo: relato de caso

Introduction: Ovotesticular disorder of sex development is a rare condition characterized by the concomitant presence of testicular and ovarian tissue, and usually presents genital ambiguity. They are chromosomally heterogeneous, and cytogenetic analyses is relevant. Objective: to report a patient from Manaus, Amazonas state, Brazil, with ovotesticular disorder of sex differentiation 46,XX and SRY-negative. Case report: patient aged 19 years, first child of non-consanguineous parents, diagnosed at birth with genital ambiguity and, without correct diagnosis, was registered a male sex. The patient underwent surgery to correct bilateral cryptorchidism, orchiopexy and colpectomy. During puberty, he developed female and male sexual characteristics. Investigation at this time revealed: laboratory (normal total testosterone and estradiol as high follicle-stimulating hormone and luteinizing hormone, histopathological (right gonad, ovarian follicles and left gonad, atrophic testicles), karyotype (46, XX) and molecular (SRY-negative). Diagnosis of ovotesticular disorder of sex development was established. The patient chose to remain male and underwent bilateral mastectomy, vaginal colpectomy and bilateral gonadectomy. Currently, the patient receives hormonal replacement therapy, followup with a multi-professional approach and awaits masculinizing genitoplasty. Discussion: For OT-DSD individuals with 46, XX, the female sex is suggested as the best sex of rearing option. Unlike the reported cases, the patient chose the male sex, since the sex at registration of birth was important in his choice. Conclusion: Cytogenetic and molecular analyses allowed us to assist in the etiological diagnosis of the patient with OT-DSD. However, molecular analyses are necessary to elucidate the genes involved in the sexual determination of this patient.

Introdução: distúrbio da diferenciação do sexo ovotesticular é uma condição rara com presença concomitante de tecido testicular e ovariano, geralmente com ambiguidade genital. Os pacientes são cromossomicamente heterogêneos e a análise citogenética é fundamental. Objetivo: relatar o caso de um paciente do município de Manaus, Amazonas, portador de distúrbio da diferenciação do sexo ovotesticular 46, XX e SRY-negativo. Caso clínico: paciente de 19 anos, primeiro filho de pais não consanguíneos, que ao nascimento foi diagnosticado com ambiguidade genital, contudo, sem diagnóstico correto, foi registrado como sendo do sexo masculino. Foi submetido a cirurgias para correção da criptoquirdia bilateral, orquidopexia e colpectomia vaginal. Na puberdade, desenvolveu características sexuais feminina e masculina. Investigação diagnóstica mostrou: exames hormonais (testosterona total e estradiol normais enquanto hormônio folículo-estimulante e hormônio luteinizante elevados), histopatológicos (gônada direita, folículos ovarianos e gônadas esquerda, testículos atróficos), cariótipo (46, XX) e molecular (SRY-negativo). O diagnóstico de distúrbio da diferenciação do sexo ovotesticular foi estabelecido. O paciente optou por permanecer no sexo masculino e submeteuse à mastectomia bilateral, colpectomia vaginal e gonadectomia bilateral. Atualmente faz reposição hormonal, acompanhamento com abordagem multiprofissional e aguarda pela genitoplastia masculinizante. Discussão: aos indivíduos DDS-OT com 46, XX é sugerido como a melhor opção de sexo, o feminino. Diferentemente dos casos relatados, o paciente optou por permanecer no sexo masculino, visto que o registro de nascimento foi importante para a sua escolha. Conclusão: análises citogenéticas e moleculares permitiu auxiliar no diagnóstico etiológico do paciente com DDS-OT, contudo, análises moleculares são necessárias para elucidação de genes envolvidos na determinação sexual desse paciente.

Síndrome de deleção 6q: relato de caso de um achado raro no Amazonas, Brasil / Deletion 6q syndrome: case report of a rare finding in Amazonas, Brazil

Objetivos: Síndrome da deleção 6q é considerada uma anomalia cromossômica rara. Assim, nosso objetivo foi relatar um caso de um menino com essa síndrome, em Manaus/Amazonas. Descrição do caso: Menino com quatro anos de idade que apresenta atraso do crescimento e do desenvolvimento neuropsicomotor, dificuldades de ganho de peso e anormalidades na retina. A análise citogenética do paciente revelou cariótipo com 46, XY, del(6)(q25-qter). Conclusões: Este relato demonstrou a importância das análises citogenéticas para o diagnóstico preciso das anomalias congênitas, pois auxiliam no encaminhamento de tratamentos adequados aos pacientes e na ampliação de conhecimento científico relacionado a essa deleção.

Aims: Deletion 6q syndrome is considered a rare chromosomal anomaly. Thus, our objective was to report a rare case of a boy with 6q deletion syndrome. Case description: 4-year-old boy with delayed growth and neuropsychomotor development, weight gain difficulties and retinal abnormalities. Karyotypic analysis of the patient revealed karyotype 46, XY, del (6) (q25-qter). That is, a deletion in the long arm of one of the chromosome 6, specifically in the distal region of the long arm of the 6q25 band up to the 6qter band. Conclusions: This report demonstrates the importance of cytogenetic analyzes for the accurate diagnosis of congenital anomalies, as they assist in referring appropriate treatments to patients and in expanding scientific knowledge related to this deletion.

Investigation of chromosomal alterations in patients with Alzheimer's disease in the state of Amazonas, Brazil / Investigação de alterações cromossômicas em pacientes com doença de Alzheimer no estado do Amazonas, Brasil

ABSTRACT Alzheimer's disease (AD) has as its main characteristic the deterioration of cerebral functions. Its etiology is still complex and undefined despite the progress made in understanding its neurological, infectious, biochemical, genetic and cytogenetic mechanisms. Considering this, the aim of this study was to investigate the presence of chromosomal alterations in the peripheral blood lymphocytes, and to verify if there was a high frequency of these alterations in patients diagnosed with AD at the University Hospital GetúLio Vargas Outpatient Clinic Araújo Lima in Manaus, Amazonas, Brazil. Among the nine patients in the AD group, only one patient did not have metaphases with chromosomal alterations (2n = 46,XX), while eight patients with AD showed numerical chromosomal alterations, classified as X chromosome aneupLoidy (2n = 45,X) and double aneupLoidy (2n = 44,X,-X,-10; 2n = 44,X,-X,-13 and 2n = 44,X,-X,-21). In the control group, no chromosomal changes were found in the karyotypes of these individuals. Therefore, the karyotypes of patients with AD undergo chromosomal alterations at different levels. These findings are being described for the first time in the population of Amazonas, and they highlight the importance of the inclusion of cytogenetic investigations in the routine management of patients with AD.

RESUMO Doença de Alzheimer (DA) tem como principal característica a deterioração das funções cerebrais. Quanto a sua etiologia ainda é complexa e indefinida, apesar do progresso alcançado na compreensão de seus mecanismos neurológicos, infecciosos, bioquímicos, genéticos e citogenéticos. Considerando isto, nós investigamos a presença de alterações cromossômicas nos Linfócitos de sangue periférico e verificamos se há uma alta frequência dessas alterações em pacientes já diagnosticados com doença de Alzheimer no Hospital Universitário Getulio Vargas / Ambulatório Araújo Lima, Manaus / Amazonas / Brasil. Assim, dos 09 pacientes do grupo DA, somente 01 paciente não apresentou metáfases com alterações cromossômicas (2n = 46,XX) enquanto que 08 pacientes com DA apresentaram alterações cromossômicas numéricas, sendo classificadas como aneupLoidia do cromossomo X (2n = 45,X) e aneupLoidia dupLa (2n = 44,X,-X,-10; 2n = 44,X,-X,-13 e 2n = 44,X,-X,-21). No grupo controle, não foram encontradas aLterações cromossômicas nos cariótipos desses indivíduos. Estes achados para a popuLação do Amazonas/ BrasiL estão sendo descritos pela primeira vez. Os cariótipos de pacientes com DA sofrem aLterações cromossômicas em diferentes níveis e demonstraram a importância das investigações citogenéticas no manejo rotineiro de pacientes com DA.

Investigation of chromosomal alterations in patients with Alzheimer's disease in the state of Amazonas, Brazil.

OBJECTIVES: Alzheimer's disease (AD) has as its main characteristic the deterioration of cerebral functions. Its etiology is still complex and undefined despite the progress made in understanding its neurological, infectious, biochemical, genetic and cytogenetic mechanisms. METHODS: Considering this, the aim of this study was to investigate the presence of chromosomal alterations in the peripheral blood lymphocytes, and to verify if there was a high frequency of these alterations in patients diagnosed with AD at the University Hospital GetúLio Vargas Outpatient Clinic Araújo Lima in Manaus, Amazonas, Brazil. RESULTS: Among the nine patients in the AD group, only one patient did not have metaphases with chromosomal alterations (2n = 46,XX), while eight patients with AD showed numerical chromosomal alterations, classified as X chromosome aneupLoidy (2n = 45,X) and double aneupLoidy (2n = 44,X,-X,-10; 2n = 44,X,-X,-13 and 2n = 44,X,-X,-21). CONCLUSION: In the control group, no chromosomal changes were found in the karyotypes of these individuals. Therefore, the karyotypes of patients with AD undergo chromosomal alterations at different levels. These findings are being described for the first time in the population of Amazonas, and they highlight the importance of the inclusion of cytogenetic investigations in the routine management of patients with AD.

Concomitance of numerical chromosomal alterations with structural in an elderly with Alzheimer's disease: a case report / Concomitância de alterações cromossômicas numéricas com estruturais em idoso com doença de Alzheimer: relato de caso

AIMS: To report the first case the concomitance of numerical chromosomal abnormalities with structural as well as chromosomal abnormalities structural in a patient diagnosed with Alzheimer disease in Manaus/Amazonas. CASE DESCRIPTION: A male patient with 76 years of age was diagnosed with diagnosis of cognitive disorder- Alzheimer's disease with late onset - temporal variant after laboratory, physical and imaging exams. Cytogenetic analysis was requested for this patient, revealing the presence the concomitant of numerical and structural chromosomal abnormalities with metaphase cells composed of 45 chromosomes with the loss of one of the homologues of chromosome 21 (monosomy) and a deletion of the long arm of one of the homologues of chromosome 1 [45, XY, -21, del (1) (q?)] and metaphase cells containing 46 chromosomes with a deletion of the long arm of one of the homologues of chromosome 15 [(46, XY, del (15) (q?)]. Currently, the patient is in outpatient treatment for maintenance and control of the disease. CONCLUSIONS: Our study has underlined that karyotyping is one of the fundamental investigations for patients with Alzheimer's disease. It highlighted, in the form of a chromosomal abnormality, may have been the risk factor in Alzheimer's disease.

OBJETIVOS: Relatar o primeiro caso de concomitância de anormalidade cromossômica numérica com anormalidade cromossômica estruturais em um paciente diagnosticado com doença de Alzheimer em Manaus/Amazonas DESCRIÇÃO DO CASO: Um paciente do sexo masculino com 76 anos de idade foi diagnosticado com distúrbio cognitivo - doença de Alzheimer com início tardio - variante temporal, após exames laboratoriais, físicos e de imagem. Análises citogenéticas foi solicitado para esse paciente, revelando a presença concomitante de anormalidades cromossômicas numéricas e estruturais com células metafásicas compostas por 45 cromossomos, com a perda de um dos homólogos do cromossomo 21 (monossomia) e a deleção do braço longo de um dos homólogos do cromossomo 1 [45, XY, -21, del (1) (q?)] e células metafásicas contendo 46 cromossomos apresentando deleção no braço longo de um dos homólogos do cromossomo 15 [(46, XY, del (15) (q?)] Atualmente, o paciente encontra-se em tratamento ambulatorial para manutenção e controle da doença. CONCLUSÕES: Nosso estudo revelam que a cariotipagem é uma das investigações fundamentais para pacientes com doença de Alzheimer. A anormalidade cromossômicas pode ter sido o fator de risco para a doença de Alzheimer.

Differential chromosomal organization between Saguinus midas and Saguinus bicolor with accumulation of differences the repetitive sequence DNA.

Saguinus is the largest and most complex genus of the subfamily Callitrichinae, with 23 species distributed from the south of Central America to the north of South America with Saguinus midas having the largest geographical distribution while Saguinus bicolor has a very restricted one, affected by the population expansion in the state of Amazonas. Considering the phylogenetic proximity of the two species along with evidence on the existence of hybrids between them, as well as cytogenetic studies on Saguinus describing a conserved karyotypic macrostructure, we carried out a physical mapping of DNA repeated sequences in the mitotic chromosome of both species, since these sequences are less susceptible to evolutionary pressure and possibly perform an important function in speciation. Both species presented 2n = 46 chromosomes; in S. midas, chromosome Y is the smallest. Multiple ribosomal sites occur in both species, but chromosome pairs three and four may be regarded as markers that differ the species when subjected to G banding and distribution of retroelement LINE 1, suggesting that it may be cytogenetic marker in which it can contribute to identification of first generation hybrids in contact zone. Saguinus bicolor also presented differences in the LINE 1 distribution pattern for sexual chromosome X in individuals from different urban fragments, probably due to geographical isolation. In this context, cytogenetic analyses reveal a differential genomic organization pattern between species S. midas and S. bicolor, in addition to indicating that individuals from different urban fragments have been accumulating differences because of the isolation between them.

Karyotypic Comparison of Hoplias malabaricus (Bloch, 1794) (Characiformes, Erythrinidae) in Central Amazon.

Hoplias malabaricus comprises seven karyomorphs (A-G) and evolutionary units have been described in some of them. In this study, the karyotypic composition and genomic organization of individual H. malabaricus from Central Amazon are described and to verify whether they can be classified according to known karyomorphs. Individuals from the Ducke Reserve have 2n = 42 chromosomes, similar to karyomorph A. Individuals from Catalão Lake and Marchantaria Island exhibit 2n = 40 chromosomes, similar to karyomorph C. Regarding the constitutive heterochromatin, individuals from all locations present centromeric/pericentromeric blocks, in addition to some bitelomeric and interstitial markings. The number of chromosomes with nucleolar organizer region, 5S rDNA and 18S rDNA sites varied among the different locations. The Rex 3 element has a compartmentalized distribution at the terminal and centromeric regions of most chromosomes, with subtle differences among populations. Fluorescence in situ hybridization performed with a telomeric probe allowed the detection of these regions only at the terminal ends of the chromosomes. Thus, only the chromosomal macrostructure (karyomorphs A-G) is not sufficient to establish evolutionary units within the H. malabaricus group, considering differences in the genome organization that are found among their populations. Such differences in the genomic organization could be mainly caused by the sedentary habits of this species.

Intense genomic reorganization in the genus Oecomys (Rodentia, Sigmodontinae): comparison between DNA barcoding and mapping of repetitive elements in three species of the Brazilian Amazon.

Oecomys Thomas, 1906 is one of the most diverse and widely distributed genera within the tribe Oryzomyini. At least sixteen species in this genus have been described to date, but it is believed this genus contains undescribed species. Morphological, molecular and cytogenetic study has revealed an uncertain taxonomic status for several Oecomys species, suggesting the presence of a complex of species. The present work had the goal of contributing to the genetic characterization of the genus Oecomys in the Brazilian Amazon. Thirty specimens were collected from four locations in the Brazilian Amazon and three nominal species recognized: Oecomys auyantepui (Tate, 1939), Oecomys bicolor (Tomes, 1860) and Oecomys rutilus (Anthony, 1921). COI sequence analysis grouped Oecomys auyantepui, Oecomys bicolor and Oecomys rutilus specimens into one, three and two clades, respectively, which is consistent with their geographic distribution. Cytogenetic data for Oecomys auyantepui revealed the sympatric occurrence of two different diploid numbers, 2n=64/NFa=110 and 2n=66/NFa=114, suggesting polymorphism while Oecomys bicolor exhibited 2n=80/NFa=142 and Oecomys rutilus 2n=54/NFa=90. The distribution of constitutive heterochromatin followed a species-specific pattern. Interspecific variation was evident in the chromosomal location and number of 18S rDNA loci. However, not all loci showed signs of activity. All three species displayed a similar pattern for 5S rDNA, with only one pair carrying this locus. Interstitial telomeric sites were found only in Oecomys auyantepui. The data presented in this work reinforce intra- and interspecific variations observed in the diploid number of Oecomys species and indicate that chromosomal rearrangements have led to the appearance of different diploid numbers and karyotypic formulas.

Comparative Cytotaxonomy of Two Species of Fish from the Genus Satanoperca Reveals the Presence of a B Chromosome.

The taxonomy of Satanoperca spp. is still unresolved, especially because coloring, one of the main diagnostic characters, is variable among species of this genus. Thus, the aim of this study was to elucidate the relationship between the genome and the organization of the chromosome in two Satanoperca species. Our main goal was to develop a method to better differentiate taxa and understand the evolution of Satanoperca jurupari and Satanoperca lilith karyotypes, which we analyzed with classical and molecular cytogenetics. Both species have the same diploid number (2n) of 48 and location of 5S rDNA sites on pair 5. Nonetheless, the distribution of heterochromatin and 18S rDNA sites followed a species-specific pattern. The interstitial telomeric sites were not highlighted in either species. Regardless, a single B chromosome was identified in some metaphases of S. lilith. These data show that Satanoperca species harbor chromosomal features that can be used to identify the two species of Satanoperca studied here, allowing for the use of cytogenetic markers to make taxonomic inferences within the genus.

Genomic Organization Under Different Environmental Conditions: Hoplosternum Littorale as a Model.

The Amazon has abundant rivers, streams, and floodplains in both polluted and nonpolluted environments, which show great adaptability. Thus, the goal of this study was to map repetitive DNA sequences in both mitotic chromosomes and erythrocyte micronuclei of tamoatás from polluted and nonpolluted environments and to assess the possible genotoxic effects of these environments. Individuals were collected in Manaus, Amazonas (AM), and submitted to classical and molecular cytogenetic techniques, as well as to a blood micronucleus test. Diploid number equal to 60 chromosomes are present in all individuals, with 18S ribosomal DNA sites present in one chromosome pair and no interstitial telomeric sites on chromosomes. The micronucleus test showed no significant differences in pairwise comparisons between environments or collection sites, but the Rex3 retroelement was dispersed on the chromosomes of individuals from unpolluted environments and compartmentalized in individuals from polluted environments. Divergent numbers of 5S rDNA sites are present in individuals from unpolluted and polluted environments. The mapping of repetitive sequences revealed that micronuclei have different compositions both intra- and interindividually that suggests different regions are lost in the formation of micronuclei, and no single fragile region undergoes breaks, although repetitive DNA elements are involved in this process.

Karyoevolution in Potamorhina (Cope, 1878) (Ostariophysi, Curimatidae): Using Repetitive DNA for the Elucidation of Genome Organization.

Some families of Characiformes present the tendency toward stability of the karyotypic macrostructure as Curimatidae, which contains species with a 2n = 54 karyotype and metacentric and submetacentric chromosomes, however, some Potamorhina species contradict to this tendency. Some species of the central Amazon exhibit different diploid number and show intraspecific variation in the location of heterochromatin. By performing cytogenetic characterization by localization of heterochromatin and the nucleolus organizer region, as well as physical chromosome mapping using probes targeting 5S and 18S ribosomal DNA (rDNA), retroelement of Xiphophorus 1 (Rex1), Rex3, telomeres, and tropomyosin 1 (TPM1), we attempted to understand the evolutionary mechanisms involved in the differentiation of the Potamorhina species. The analyses showed that the heterochromatic regions of the examined species are distinct and transposable elements are involved in this evolutionary process, considering that the dynamic regions of the genome appear to include the terminal regions and particularly the heterochromatin-rich centromeric regions, which are involved in fission and fusion processes and promote the differentiation of chromosome pairs that bear ribosomal sites; these pairs were similar in the central Amazon species. Thus, we propose a phylogeny for this genus.

Cytogenetic analyses of five amazon lizard species of the subfamilies Teiinae and Tupinambinae and review of karyotyped diversity the family Teiidae.

Lizards of the family Teiidae (infraorder Scincomorpha) were formerly known as Macroteiidae. There are 13 species of such lizards in the Amazon, in the genera Ameiva (Meyer, 1795), Cnemidophorus (Wagler, 1830), Crocodilurus (Spix, 1825), Dracaena (Daudin, 1801), Kentropyx (Spix, 1825) and Tupinambis (Daudin, 1802). Cytogenetic studies of this group are restricted to karyotype macrostructure. Here we give a compilation of cytogenetic data of the family Teiidae, including classic and molecular cytogenetic analysis of Ameiva ameiva (Linnaeus, 1758), Cnemidophorus sp.1, Kentropyx calcarata (Spix, 1825), Kentropyx pelviceps (Cope, 1868) and Tupinambis teguixin (Linnaeus, 1758) collected in the state of Amazonas, Brazil. Ameiva ameiva, Kentropyx calcarata and Kentropyx pelviceps have 2n=50 chromosomes classified by a gradual series of acrocentric chromosomes. Cnemidophorus sp.1 has 2n=48 chromosomes with 2 biarmed chromosomes, 24 uniarmed chromosomes and 22 microchromosomes. Tupinambis teguixin has 2n=36 chromosomes, including 12 macrochromosomes and 24 microchromosomes. Constitutive heterochromatin was distributed in the centromeric and terminal regions in most chromosomes. The nucleolus organizer region was simple, varying in its position among the species, as evidenced both by AgNO3 impregnation and by hybridization with 18S rDNA probes. The data reveal a karyotype variation with respect to the diploid number, fundamental number and karyotype formula, which reinforces the importance of increasing chromosomal analyses in the Teiidae.