mayana Santos - Academia.edu (original) (raw)
Papers by mayana Santos
American Journal of Medical Genetics, 1995
There are some indications that Becker muscular dystrophy (BMD) might be related to mental disord... more There are some indications that Becker muscular dystrophy (BMD) might be related to mental disorders and mental retardation (MR). To investigate this question, we made a standardized psychiatric and intellectual level assessment of 22 BMD patients in comparison with 22 limb-girdle muscular dystrophy (LGMD) patients. There were not significant differences between the two groups. Twelve patients (54.5%) in each group received at least one lifetime psychiatric diagnosis, the most frequent being depressive disorders. The intelligence quotient means for BMD was 85.9 and 87.8 for LGMD. There was one case of mild MR among BMD patients and two cases among LGMD patients. © 1995 Wiley-Liss, Inc.
Journal of Medical Genetics, 1996
American Journal of Medical Genetics, 2004
European Journal of Human Genetics, 2001
Annals of Human Genetics, 2009
SPOAN is an autosomal recessive neurodegenerative disorder which was recently characterized by ou... more SPOAN is an autosomal recessive neurodegenerative disorder which was recently characterized by our group in a large inbred Brazilian family with 25 affected individuals. This condition is clinically defined by: 1. congenital optic atrophy; 2. progressive spastic paraplegia with onset in infancy; and 3. progressive motor and sensory axonal neuropathy. Overall, we are now aware of 68 SPOAN patients (45 females and 23 males, with age ranging from 5 to 72 years), 44 of which are presented here for the first time. They were all born in the same geographic micro region. Those 68 patients belong to 43 sibships, 40 of which exhibit parental consanguinity. Sixty-one patients were fully clinically evaluated and 64 were included in the genetic investigation. All molecularly studied patients are homozygotes for D11S1889 at 11q13. This enabled us to reduce the critical region for the SPOAN gene from 4.8 to 2.3 Mb, with a maximum two point lod score of 33.2 (with marker D11S987) and of 27.0 (with marker D11S1889). Three genes located in this newly defined critical region were sequenced, but no pathogenic mutation was detected. The gene responsible for SPOAN remains elusive.
Ciencia Rural, 2009
Duchenne muscular dystrophy (DMD) is one type of human's muscular dystrophy characterized by a ge... more Duchenne muscular dystrophy (DMD) is one type of human's muscular dystrophy characterized by a genetic disorder linked to the X chromosome. The Golden Retriever muscular dystrophic (GRMD) has been extensively studied and considered the best resembling model to the human disease. Therefore, for identifying internal organs abnormality in GRMD, abdominal and pelvic ultrasonography was performed in 24 golden retriever dogs, either healthy or muscular dystrophic in different levels of disease. The GRMD ultrasonographic exams diagnosed moderate to severe liver enlargement, including hepatic vessels and their branches and increase of echogenicity in gallbladder and urinary bladder. However was not-clearly recognized pathologic images from spleen and aortic vessels were accessed. Therefore, we believe, the ultrasonographic exam was an useful procedure to the assessment of abdominal organs in dogs affected by muscular dystrophy.
American Journal of Medical Genetics, 1998
It has been suggested that the serotonin transporter (5-hydroxytryptamine-transporter or 5-HTT) m... more It has been suggested that the serotonin transporter (5-hydroxytryptamine-transporter or 5-HTT) may be involved in the pathogenesis of affective disorders. Recently, Collier et al. (1996) found that the frequency of the low-activity short variant (s) of the 5-HTT-linked polymorphic region (5-HTTLPR) was higher among patients with affective disorders than in normal controls. However, since the observed level of significance was not high, they suggest that these findings should be replicated in independent samples. We have analyzed 86 unrelated patients (47 with bipolar disorder and 39 with schizophrenia) and 98 normal controls from the Brazilian population for the 5-HTTLPR. Statistical analysis revealed that the genotypes (LL, Ls, ss) as well as the estimated allele frequencies (L,s) did not differ significantly among the three studied groups or between bipolar and normal controls. In addition, although not statistically significant, the genotype ss in our sample was less frequent among our bipolar patients than in our normal controls (12.8% versus 16.3%) which is the opposite of what was found by Collier et al. (24% versus 18%) in the European study. Although it will be important to extend the present analysis in a larger sample, our preliminary results suggest that the 5-HTTLPR does not seem to play a major role in the genetics of bipolar and schizophrenic disorders at least in this group of Brazilian psychiatric patients.
American Journal of Medical Genetics, 1999
... Correspondence: MR Passos-Bueno, Centro de Estudos do Genoma Humano, Departamento de Biologia... more ... Correspondence: MR Passos-Bueno, Centro de Estudos do Genoma Humano, Departamento de Biologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil. Publication History. Issue published online: 25 OCT 1999; Article first published online: 25 OCT ...
American Journal of Medical Genetics, 1999
The autosomal recessive limb-girdle muscular dystrophies (AR-LGMDs) are a heterogeneous group of ... more The autosomal recessive limb-girdle muscular dystrophies (AR-LGMDs) are a heterogeneous group of disorders of progressive weakness of the pelvic and shoulder girdle musculature. The clinical course is characterized by great variability, ranging from severe forms with onset in the first decade and rapid progression resembling clinically Xp21 Duchenne muscular dystrophy (DMD) to milder forms with later onset and slower course. Eight genes are mapped for the AR-LGMDs; they are: LGMD2A (CAPN3) at 15q, LGMD2B (dysferlin) at 2p, LGMD2C (gamma-SG) at 13q, LGMD2D (alpha-SG) at 17q, LGMD2E (beta-SG) at 4q, LGMD2F (6-SG) at 5q, LGMD2G at 17q, and more recently LGMD2H at 9q. The LGMD2F (delta-SG) and LGMD2G genes were mapped in Brazilian AR-LGMD families. Linkage analysis in two unlinked families excluded the eight AR-LGMD genes, indicating that there is at least one more gene responsible for AR-LGMD. We have analyzed 140 patients (from 40 families) affected with one of seven autosomal recessive LGMD loci, that is, from LGMD2A to LGMD2G. The main observations were: 1) all LGMD2E and LGMD2F patients had a severe condition, but considerable inter- and intra-familial clinical variability was observed among patients from all other groups; 2) serum CK activities showed the highest values in LGMD2D (alpha-SG) patients among sarcoglycanopathies and LGMD2B (dysferlin) patients among nonsarcoglycanopathies; 3) comparison between LGMD2A (CAPN3) and LGMD2B (dysferlin) showed that the first have on average a more severe course and have calf hypertrophy more frequently (86% versus 13%); and 4) inability to walk on toes was observed in approximately 70% of LGMD2B patients.
Annals of Neurology, 2005
We report an autosomal recessive neurodegenerative disorder in 25 white members from a large inbr... more We report an autosomal recessive neurodegenerative disorder in 25 white members from a large inbred Brazilian family, 22 of whom were evaluated clinically. This condition is characterized by (1) subnormal vision secondary to apparently nonprogressive congenital optic atrophy; (2) onset of progressive spastic paraplegia in infancy; (3) onset of progressive motor and sensory axonal neuropathy in late childhood/early adolescence; (4) dysarthria starting in the third decade of life; (5) exacerbated acoustic startle response; and (6) progressive joint contractures and spine deformities. Motor handicap was severe, and all patients were wheelchair bound after 15 years old. We performed a genome-wide screen including 25 affected individuals and 49 of their unaffected relatives. Linkage was detected at 11q13 region with a maximum logarithm of odds score of +14.43, obtained with marker D11S1883. The candidate region, which lies between D11S1908 and D11S1889, encompasses ∼4.8Mb and has more than 100 genes and expressed sequences. We propose the acronym SPOAN (spastic paraplegia, optic atrophy, and neuropathy) for this complex syndrome. Ann Neurol 2005;57:730–737
Human Mutation, 1997
Duchenne (DMD) and Becker (BMD) type muscular dystrophies are allelic X-linked recessive disorder... more Duchenne (DMD) and Becker (BMD) type muscular dystrophies are allelic X-linked recessive disorders caused by mutations in the gene encoding dystrophin. About 65% of the cases are caused by deletions, while 5-10% are duplications. The remaining 30% of affected individuals may have smaller mutations (point mutations or small deletions/insertions) which cannot be identified by current diagnostic screening strategies. In order to look for pathogenic small mutations in the dystrophin gene, we have screened the 18 exons located in the hot spot region of this gene through two different single strand conformation polymorphism (SSCP) conditions. Five different pathogenic mutations were identified in 6 out of 192 DMD/BMD patients without detectable deletions: 2 nonsense, 1 bp insertion, 1 bp deletion and 1 intronic. Except for the intronic change, which alters a splice site, all the others cause a premature stop codon. In addition, 8 apparently neutral changes were identified. However, interestingly, one of them was not identified in 195 normal chromosomes, although it was previously described in a DMD patient from a different population. The possibility that this mutation may be pathogenic is discussed. Except for two neutral changes, all the others are apparently here described for the first time.
American Journal of Medical Genetics, 1989
American Journal of Human Genetics, 1997
Human Molecular Genetics, 1993
Human Molecular Genetics, 1995
The purpose of this investigation was to analyze the CTG expansion in muscle as compared to lymph... more The purpose of this investigation was to analyze the CTG expansion in muscle as compared to lymphocytes DNA in a sample of selected myotonic dystrophy (DM) patients of different ages and degrees of clinical severity, ranging from severe congenital to minimally affected. Results from the present study showed that the size of the CTG repeat was markedly larger in skeletal muscle than in lymphocytes in all DM patients. In contrast to lymphocytes, no significant correlation was found between the size of the CTG expansion in muscle and age at onset. In addition, large expansions were observed in muscle from all adult symptomatic patients independently of the presence of muscle weakness, which raises the question of the value of analyzing CTG expansions in muscle for predicting the severity of the phenotype. Differences between the size of the CTG expansions in muscle as compared to lymphocytes were smaller in affected children suggesting an apparent tendency to increase with aging and reaching a plateau in adulthood.
Human Molecular Genetics, 1998
American Journal of Medical Genetics, 1995
There are some indications that Becker muscular dystrophy (BMD) might be related to mental disord... more There are some indications that Becker muscular dystrophy (BMD) might be related to mental disorders and mental retardation (MR). To investigate this question, we made a standardized psychiatric and intellectual level assessment of 22 BMD patients in comparison with 22 limb-girdle muscular dystrophy (LGMD) patients. There were not significant differences between the two groups. Twelve patients (54.5%) in each group received at least one lifetime psychiatric diagnosis, the most frequent being depressive disorders. The intelligence quotient means for BMD was 85.9 and 87.8 for LGMD. There was one case of mild MR among BMD patients and two cases among LGMD patients. © 1995 Wiley-Liss, Inc.
Journal of Medical Genetics, 1996
American Journal of Medical Genetics, 2004
European Journal of Human Genetics, 2001
Annals of Human Genetics, 2009
SPOAN is an autosomal recessive neurodegenerative disorder which was recently characterized by ou... more SPOAN is an autosomal recessive neurodegenerative disorder which was recently characterized by our group in a large inbred Brazilian family with 25 affected individuals. This condition is clinically defined by: 1. congenital optic atrophy; 2. progressive spastic paraplegia with onset in infancy; and 3. progressive motor and sensory axonal neuropathy. Overall, we are now aware of 68 SPOAN patients (45 females and 23 males, with age ranging from 5 to 72 years), 44 of which are presented here for the first time. They were all born in the same geographic micro region. Those 68 patients belong to 43 sibships, 40 of which exhibit parental consanguinity. Sixty-one patients were fully clinically evaluated and 64 were included in the genetic investigation. All molecularly studied patients are homozygotes for D11S1889 at 11q13. This enabled us to reduce the critical region for the SPOAN gene from 4.8 to 2.3 Mb, with a maximum two point lod score of 33.2 (with marker D11S987) and of 27.0 (with marker D11S1889). Three genes located in this newly defined critical region were sequenced, but no pathogenic mutation was detected. The gene responsible for SPOAN remains elusive.
Ciencia Rural, 2009
Duchenne muscular dystrophy (DMD) is one type of human's muscular dystrophy characterized by a ge... more Duchenne muscular dystrophy (DMD) is one type of human's muscular dystrophy characterized by a genetic disorder linked to the X chromosome. The Golden Retriever muscular dystrophic (GRMD) has been extensively studied and considered the best resembling model to the human disease. Therefore, for identifying internal organs abnormality in GRMD, abdominal and pelvic ultrasonography was performed in 24 golden retriever dogs, either healthy or muscular dystrophic in different levels of disease. The GRMD ultrasonographic exams diagnosed moderate to severe liver enlargement, including hepatic vessels and their branches and increase of echogenicity in gallbladder and urinary bladder. However was not-clearly recognized pathologic images from spleen and aortic vessels were accessed. Therefore, we believe, the ultrasonographic exam was an useful procedure to the assessment of abdominal organs in dogs affected by muscular dystrophy.
American Journal of Medical Genetics, 1998
It has been suggested that the serotonin transporter (5-hydroxytryptamine-transporter or 5-HTT) m... more It has been suggested that the serotonin transporter (5-hydroxytryptamine-transporter or 5-HTT) may be involved in the pathogenesis of affective disorders. Recently, Collier et al. (1996) found that the frequency of the low-activity short variant (s) of the 5-HTT-linked polymorphic region (5-HTTLPR) was higher among patients with affective disorders than in normal controls. However, since the observed level of significance was not high, they suggest that these findings should be replicated in independent samples. We have analyzed 86 unrelated patients (47 with bipolar disorder and 39 with schizophrenia) and 98 normal controls from the Brazilian population for the 5-HTTLPR. Statistical analysis revealed that the genotypes (LL, Ls, ss) as well as the estimated allele frequencies (L,s) did not differ significantly among the three studied groups or between bipolar and normal controls. In addition, although not statistically significant, the genotype ss in our sample was less frequent among our bipolar patients than in our normal controls (12.8% versus 16.3%) which is the opposite of what was found by Collier et al. (24% versus 18%) in the European study. Although it will be important to extend the present analysis in a larger sample, our preliminary results suggest that the 5-HTTLPR does not seem to play a major role in the genetics of bipolar and schizophrenic disorders at least in this group of Brazilian psychiatric patients.
American Journal of Medical Genetics, 1999
... Correspondence: MR Passos-Bueno, Centro de Estudos do Genoma Humano, Departamento de Biologia... more ... Correspondence: MR Passos-Bueno, Centro de Estudos do Genoma Humano, Departamento de Biologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil. Publication History. Issue published online: 25 OCT 1999; Article first published online: 25 OCT ...
American Journal of Medical Genetics, 1999
The autosomal recessive limb-girdle muscular dystrophies (AR-LGMDs) are a heterogeneous group of ... more The autosomal recessive limb-girdle muscular dystrophies (AR-LGMDs) are a heterogeneous group of disorders of progressive weakness of the pelvic and shoulder girdle musculature. The clinical course is characterized by great variability, ranging from severe forms with onset in the first decade and rapid progression resembling clinically Xp21 Duchenne muscular dystrophy (DMD) to milder forms with later onset and slower course. Eight genes are mapped for the AR-LGMDs; they are: LGMD2A (CAPN3) at 15q, LGMD2B (dysferlin) at 2p, LGMD2C (gamma-SG) at 13q, LGMD2D (alpha-SG) at 17q, LGMD2E (beta-SG) at 4q, LGMD2F (6-SG) at 5q, LGMD2G at 17q, and more recently LGMD2H at 9q. The LGMD2F (delta-SG) and LGMD2G genes were mapped in Brazilian AR-LGMD families. Linkage analysis in two unlinked families excluded the eight AR-LGMD genes, indicating that there is at least one more gene responsible for AR-LGMD. We have analyzed 140 patients (from 40 families) affected with one of seven autosomal recessive LGMD loci, that is, from LGMD2A to LGMD2G. The main observations were: 1) all LGMD2E and LGMD2F patients had a severe condition, but considerable inter- and intra-familial clinical variability was observed among patients from all other groups; 2) serum CK activities showed the highest values in LGMD2D (alpha-SG) patients among sarcoglycanopathies and LGMD2B (dysferlin) patients among nonsarcoglycanopathies; 3) comparison between LGMD2A (CAPN3) and LGMD2B (dysferlin) showed that the first have on average a more severe course and have calf hypertrophy more frequently (86% versus 13%); and 4) inability to walk on toes was observed in approximately 70% of LGMD2B patients.
Annals of Neurology, 2005
We report an autosomal recessive neurodegenerative disorder in 25 white members from a large inbr... more We report an autosomal recessive neurodegenerative disorder in 25 white members from a large inbred Brazilian family, 22 of whom were evaluated clinically. This condition is characterized by (1) subnormal vision secondary to apparently nonprogressive congenital optic atrophy; (2) onset of progressive spastic paraplegia in infancy; (3) onset of progressive motor and sensory axonal neuropathy in late childhood/early adolescence; (4) dysarthria starting in the third decade of life; (5) exacerbated acoustic startle response; and (6) progressive joint contractures and spine deformities. Motor handicap was severe, and all patients were wheelchair bound after 15 years old. We performed a genome-wide screen including 25 affected individuals and 49 of their unaffected relatives. Linkage was detected at 11q13 region with a maximum logarithm of odds score of +14.43, obtained with marker D11S1883. The candidate region, which lies between D11S1908 and D11S1889, encompasses ∼4.8Mb and has more than 100 genes and expressed sequences. We propose the acronym SPOAN (spastic paraplegia, optic atrophy, and neuropathy) for this complex syndrome. Ann Neurol 2005;57:730–737
Human Mutation, 1997
Duchenne (DMD) and Becker (BMD) type muscular dystrophies are allelic X-linked recessive disorder... more Duchenne (DMD) and Becker (BMD) type muscular dystrophies are allelic X-linked recessive disorders caused by mutations in the gene encoding dystrophin. About 65% of the cases are caused by deletions, while 5-10% are duplications. The remaining 30% of affected individuals may have smaller mutations (point mutations or small deletions/insertions) which cannot be identified by current diagnostic screening strategies. In order to look for pathogenic small mutations in the dystrophin gene, we have screened the 18 exons located in the hot spot region of this gene through two different single strand conformation polymorphism (SSCP) conditions. Five different pathogenic mutations were identified in 6 out of 192 DMD/BMD patients without detectable deletions: 2 nonsense, 1 bp insertion, 1 bp deletion and 1 intronic. Except for the intronic change, which alters a splice site, all the others cause a premature stop codon. In addition, 8 apparently neutral changes were identified. However, interestingly, one of them was not identified in 195 normal chromosomes, although it was previously described in a DMD patient from a different population. The possibility that this mutation may be pathogenic is discussed. Except for two neutral changes, all the others are apparently here described for the first time.
American Journal of Medical Genetics, 1989
American Journal of Human Genetics, 1997
Human Molecular Genetics, 1993
Human Molecular Genetics, 1995
The purpose of this investigation was to analyze the CTG expansion in muscle as compared to lymph... more The purpose of this investigation was to analyze the CTG expansion in muscle as compared to lymphocytes DNA in a sample of selected myotonic dystrophy (DM) patients of different ages and degrees of clinical severity, ranging from severe congenital to minimally affected. Results from the present study showed that the size of the CTG repeat was markedly larger in skeletal muscle than in lymphocytes in all DM patients. In contrast to lymphocytes, no significant correlation was found between the size of the CTG expansion in muscle and age at onset. In addition, large expansions were observed in muscle from all adult symptomatic patients independently of the presence of muscle weakness, which raises the question of the value of analyzing CTG expansions in muscle for predicting the severity of the phenotype. Differences between the size of the CTG expansions in muscle as compared to lymphocytes were smaller in affected children suggesting an apparent tendency to increase with aging and reaching a plateau in adulthood.
Human Molecular Genetics, 1998