RESUMO
A 25-year-old woman with a mosaic 45,X/47XX,+14 karyotype is reported. She presented with short stature, short downward slanting palpebral fissures, broad nasal bridge, mouth with downturned corners, short and wide neck, swirly hyperpigmentation of the skin, and body asymmetry secondary to right hemihyperplasia. As there was an admixture of 45,X and trisomy 14, it was not possible to determine the cell line that had the greatest influence on the phenotype. We postulate that the proposita's survival until the third decade was owing to the chromosomal complementation of both aneuploidy cell lines. To our knowledge, this chromosomal association has not been previously reported.
Assuntos
Cromossomos Humanos Par 14 , Mosaicismo , Trissomia , Síndrome de Turner/genética , Adulto , Feminino , HumanosRESUMO
In the present study we describe a patient with characteristic brachydactily, developmental delay and interstitial del 13q22-->q31. After the review of the literature, few cases sharing similar chromosomal deletions were found and they displayed little resemblance with our patient. We discuss the phenotype correlation among the deleted regions in such cases.
Assuntos
Anormalidades Múltiplas/genética , Deleção Cromossômica , Cromossomos Humanos Par 13/genética , Fácies , Anormalidades Múltiplas/patologia , Criança , Bandeamento Cromossômico , Anormalidades Craniofaciais/patologia , Deformidades do Pé/patologia , Transtornos do Crescimento/patologia , Deformidades Congênitas da Mão/diagnóstico por imagem , Deformidades Congênitas da Mão/patologia , Humanos , Cariotipagem , Transtornos do Desenvolvimento da Linguagem/patologia , Masculino , Transtornos Psicomotores/patologia , Radiografia , Dedos do Pé/anormalidades , Dedos do Pé/diagnóstico por imagemRESUMO
We studied in 39 carriers of 26 reciprocal translocations (including five de novo and seven of indeterminate occurrence) the metaphase localization of the derivative chromosomes, their normal non-homologous counterparts (here called A and B), and two control pairs (C and D). In eight familial translocations, we analysed two to five carriers. We digitally captured 10 G-banded lymphocyte metaphases per individual and measured in microns the largest diameter (d) of the metaphase and six intercentromeric distances: (1) der A<-->der B (problem distance 1, pd1), (2) der A<-->B (pd2), (3) der B<-->A (pd3), (4) A<-->B (control distance 1, cd1), (5) the smaller distance between C and D (cd2) and (6) the largest distance between C and D (cd3); in addition, the average between C and D (cd4) was calculated. We used the formula Delta = 100(cd - pd)/d 12 times per metaphase, compared each pd vs. each cd, and tested the differences by the Wilcoxon matched-pair test. Although, in the whole sample there were not significant differences respect to cd1, this distance emerged as the proper control. In the eight familial translocations, the three pd vs. cd1 comparisons revealed that in 19/24 times the pd was smaller but only once reached significance (cd1 vs. pd2 in t[3;4]). In the analysis per individual the pd was smaller than cd1 in 19 (pd1), 22 (pd2) and 22 (pd3) cases although only twice reached significance. We conclude that in some translocations, the derivative chromosomes actually lie close from each other or from a normal non-homologous counterpart.
Assuntos
Cromossomos Humanos , Metáfase , Translocação Genética , Humanos , Cariotipagem , MicroscopiaRESUMO
There have only been eight patients with 6p pure trisomy involving different segments: four cases resulted from a translocation or insertion and four were due to an intrachromosomal duplication. We report here the first postnatally ascertained patient with a pure 6p partial trisomy due to an interchromosomal insertion (16;6)(p12;p21.2p23)mat. This rearrangement was confirmed by fluorescent in situ hybridization (FISH) with whole chromosome 6 and 16 painting probes. The clinical findings in the present patient were similar to those observed in previous cases, including craniofacial dysmorphism, minor anomalies, and lack of severe anatomical defects; yet, the unspecificity of many of these features prevented us from delineating the 6p pure trisomy syndrome.
Assuntos
Cromossomos Humanos Par 6 , Anormalidades Craniofaciais/genética , Trissomia , Cromossomos Humanos Par 16 , Feminino , Humanos , Lactente , Cariotipagem , MasculinoRESUMO
An azoospermic male was found to have, by means of banding techniques, a 45,X karyotype including a monocentric chromosome 21 with an euchromatic short arm that looked similar to Yp. This rearranged chromosome was further characterized by FISH with a whole Y chromosome paint and the alphoid repeats DYZ3 and D13Z1/D21Z1; the former probe gave a positive signal onto such a peculiar arm without spreading into the long arm, whereas the alphoid repeats revealed an apparent compound centromere with Y- and 21-sequences. Therefore, an unbalanced Y;21 whole arm translocation was concluded and the karyotype written as 45,X.ish der(Y;21)(p10;q10)(wcpY+,DYZ3+,D13Z1/D21Z1+). This patient represents the first case of a Y;21 translocation in an apparent 45,X male, constitutes the fifth instance of a 45,X sterile male, and conforms to previously established karyotype-phenotype correlations.
Assuntos
Cromossomos Humanos Par 21/genética , Cromossomos Humanos X/genética , Cromossomos Humanos Y/genética , Oligospermia/genética , Aberrações dos Cromossomos Sexuais , Translocação Genética , Adulto , Centrômero , Humanos , Hibridização in Situ Fluorescente , Infertilidade Masculina/genética , Cariotipagem , Masculino , FenótipoRESUMO
We report on a 16-year-old patient with Turner syndrome who presented a mos 46,X,del(X)(p22.1)[35]/45,X [19]/46,X,r(X)(p22.1q28)[6]GTG-band karyotype. The R-banding showed that the abnormal X-chromosome was inactive in all 61 cells analyzed. Fluorescence in situ hybridization with a Xp/Yp subtelomeric probe revealed that both abnormal chromosomes lacked the complementary sequences, a fact consistent with a terminal deletion. Besides, the molecular analysis of the human androgen receptor gene showed that the rearranged chromosome was paternal in origin. Since the deleted and the ring chromosomes had the same size and banding pattern, and because the former was the predominant cell line, it was inferred that the Xp- formed a ring in some cells apparently without further loss of genetic material. However, the reverse sequence and even a simultaneous origin due to a complex intrachromosomal exchange are also conceivable. The mild Turner syndrome phenotype is explained by the mosaicism and by the size of the deleted segment.