Familial Study of Paracentric Inversion in Chromosome 3p.

Aims: To describe the familial occurrence of paracentric inversion of chromosome 3. Presentation of Cases: Patient 1: Female, Caucasian, born in Southeast of Brazil, 7 years old. Born at term and asphyxia. Developmental delay; aggressive behavior and tendency toward isolation. Prominent forehead, discrete epicanthal folds, down-slanting palpebral fissures, long philtrum and hypermobility of the four limbs. Karyotype: 46,XX,inv(3)(p13p25). Patient 2: Female, Caucasian, born in Northeast of Brazil, 3 years old. Born prematurely by cesarean section, pelvic presentation and asphyxia. Severe developmental delay. Microcephaly, bilateral convergent strabismus, epicanthal folds, wide nasal bridge, micrognathia, high arched palate and nasolabial hemangioma, low set ears, hypoplastic nipples, nucal café-au-lait spots, deep plantar fold. Dysgenesis of the corpus callosum. Karyotype: 46,XX,inv(3)(p13p25). Patient 3: Male, Caucasian, born in Southeast of Brazil, 5 years. Born at term, by cesarean section, cephalic presentation. Developmental delay and flexor spasms. Dolichocephalic skull, prominent forehead, ocular hypertelorism, epicanthal folds, disproportioned and low set ears, single palmary crease in the right hand, large and elongated thumbs, hypotonia, and recurrent acute otitis. Karyotype: 46,XY,inv(3)(p13p25). Discussion: Patients presented developmental delay and dysmorphic features, but the relatives that presented the same inversion were asymptomatic. Carriers seem to have a normal reproductive fitness, without differences between males and females. Conclusion: The chromosomal rearrangements, especially balanced chromosomal alterations provide an opportunity to broaden the understanding of the structure and functional organization of chromosomes and to offer better genetic counseling for the families.

Paracentric Inversions Found in Prenatal Diagnosis

PURPOSE: This study was designed to confirm whether the paracentric inversions of fetuses and parents may be harmless. MATERIALS AND METHODS: We report 10 cases (0.14%) with paracentric inversions among 7,181 prenatal cases observed during prenatal diagnosis performed at Cheil General Hospital between January 2009 and June 2013. We used cytogenetic GTL- and RBG-banding techniques. RESULTS: Of the 10 cases, nine cases were transmitted from each of the parents, and one case was de novo. Nine cases were phenotypically normal up to one month of age after birth. One case was lost to follow-up. We present prenatal diagnosis and follow-up examination of the fetuses with paracentric inversion. CONCLUSION: Based on our cases, most paracentric inversions are considered to be harmless. The precise identification of paracentric inversions might be clinically important and helpful for genetic counseling.

A Prenatal Case of Paracentric Inversion of Chromosome 18, inv(18)(q21.1q22)

Paracentric inversion of chromosome 18 is a rare cytogenetic abnormality. The vast majority of paracentric inversions are harmless and the offspring of paracentric inversion carriers have only slightly elevated risks for unbalanced karyotypes. However, various clinical phenotypes are seen due to breakpoint variation or recombination. We report a prenatally detected case of familial paracentric inversion of chromosome 18, inv(18)(q21.1q22), with normal clinical features.

A Prenatal Case of Paracentric Inversion of Chromosome 18, inv(18)(q21.1q22)

Paracentric inversion of chromosome 18 is a rare cytogenetic abnormality. The vast majority of paracentric inversions are harmless and the offspring of paracentric inversion carriers have only slightly elevated risks for unbalanced karyotypes. However, various clinical phenotypes are seen due to breakpoint variation or recombination. We report a prenatally detected case of familial paracentric inversion of chromosome 18, inv(18)(q21.1q22), with normal clinical features.

Incidence and Karyotypes According to Each Chromosome in 13 Cases with Inversion / 대한주산의학회잡지

PURPOSE: This study was aimed to evaluate the incidence and karyotypes according to chromosome in 13 cases with inversion detected by cytogenetic analysis. METHODS: The incidence of inversion was calculated and karyotypes of inversion were classified according to each chromosome in cases with inversion detected from 390 individuals who had undergone cytogenetic analysis in Hanyang University Hospital from January 2005 to February 2009. RESULTS: The overall incidence of inversions was 3.3% (13/390). All of 13 cases were heterozygotes for inversions. Among these 13 inversions, 12 cases (92.3%) were having pericentric inversions showing karyotypes of 46,XX,inv(9)(p11q13) in 7 cases, 46,XX,inv(9)(p11q12) in 2 cases, and one cases of 46,X, inv(Y)(p11.3q11.23), t(8;9)(q24.3;q34.1), 46,X, del(Y)(q12), inv(Y)(p10q11. 23) and 46,XY, inv(8)(p21q24.1) respectively. Last one case (7.7%) was having paracentric inversion showing a karyotype of 46,XX,inv(9)(q22.1q34.3). Classification according to each chromosome in 13 cases with inversion was that 10 of 13 cases (76.9%) were located in chromosome 9 (9 cases of pericentric inversions and a case of paracentric inversions), 2 of 13 cases (15.4%) in chromosome Y and 1 of 13 cases (7.7%) in chromosome 8. CONCLUSION: Although patients are phenotypically normal, they might be inversion carriers. In high risk patients, inversions are more frequent than normal population. Various types of inversion could be in different chromosomes. Classification of types of inversion are needed for further genetic counseling according to the types.

Localization of ribosomal genes in three Pimelodus species (Siluriformes, Pimelodidae) of the São Francisco River: 5S genes as species markers and conservation of the 18S rDNA sites

Pimelodidae is one of the most representative of Neotropical catfish families. However, these fish are still poorly studied in terms of cytogenetics, especially regarding the application of more accurate techniques such as the chromosomal localization of ribosomal genes. In the present work, fluorescent in situ hybridization with 5S and 18S rDNA probes was employed for rDNA site mapping in Pimelodus sp., P. fur and P. maculatus from the São Francisco River in the Três Marias municipality - MG. The results from the application of the 18S probe confirmed the previous data obtained by silver nitrate staining, identifying a simple nucleolar organizing region system for these species. However, the labeling results from the 5S rDNA probe demonstrated a difference in the number and localization of these sites between the analyzed species. The obtained data allowed inferences on the possible processes involved in the karyotypic evolution of this genus.

A Case of Paracentric Inversion of Chromosome 12(q13q22) / 대한소아신경학회지

Paracentric inversion of chromosome 12 is a rare chromosomal aberration, which has familial inheritance in a few cases. We encountered a 2-year-old girl who presented developmental delay, failure to thrive, patent ductus arteriosus, choanal atresia, laryngomalacia, and mild facial dysmorphism. Chromosome studies from peripheral blood showed a 46, XX, inv(12)(q13q22) karyotype. The inversion was also found in her mother. The authors report the first case of paracentric inversion of chromosome 12 in Korea with a review of literature.