Comprehensive analysis of three female patients with different types of X/Y translocations and literature review.

BACKGROUND: X/Y translocations are highly heterogeneity in terms of clinical genetic effects, and most patients lack complete pedigree analysis for clinical and genetic characterization. RESULTS: This study comprehensively analyzed the clinical and genetic characteristics of three new patients with X/Y translocations. Furthermore, cases with X/Y translocations reported in the literature and studies exploring the clinical genetic effects in patients with X/Y translocations were reviewed. All three female patients were carriers of X/Y translocations with different phenotypes. The karyotype for patient 1 was 46,X,der(X)t(X;Y)(p22.33;q12)mat, patient 2 was 46,X,der(X)t(X;Y)(q21.2;q11.2)dn, and patient 3 was 46,X,der(X)t(X;Y)(q28;q11.223)t(Y;Y)(q12;q11.223)mat. C-banding analysis of all three patients revealed a large heterochromatin region in the terminal region of the X chromosome. All patients underwent chromosomal microarray analysis, which revealed the precise copy number loss or gain. Data on 128 patients with X/Y translocations were retrieved from 81 studies; the phenotype of these patients was related to the breakpoint of the chromosome, size of the deleted region, and their sex. We reclassified the X/Y translocations into new types based on the breakpoints of the X and Y chromosomes. CONCLUSION: X/Y translocations have substantial phenotypic diversity, and the genetic classification standards are not unified. With the development of molecular cytogenetics, it is necessary to combine multiple genetic methods to obtain an accurate and reasonable classification. Thus, clarifying their genetic causes and effects promptly will help in genetic counseling, prenatal diagnosis, preimplantation genetic testing, and improvement in clinical treatment strategies.

[The role of jigsaw karyotype analysis in the teaching of chromosomal recognition].

Karyotype analysis is the basic method in cytogenetics, and is also recognized as the "gold standard" for diagnosing chromosomal disorders. The teaching and training for traditional karyotyping analysis is time-consuming and even boring. The individual's ability for mastering the chromosome morphology can vary greatly. Therefore, it is necessary to improve the teaching method. On the basis of the traditional method, we have added auxiliary analysis software during the teaching. This type of splicing karyotype teaching has increased the students' interest and improved their ability for karyotyping, allowing them to quickly remember the characteristic bands of chromosomes. Through enhanced memory of a large number of karyotypic images, the students' ability to recognize individual chromosomes has improved.

Infertility in a man with oligoasthenozoospermia associated with mosaic chromosome 22q11 deletion.

BACKGROUND: A 30-year-old oligoasthenozoospermia man was found to have unbalance mosaic translocation between chromosome 22 and four other chromosomes (5, 6, 13, and 15) during the investigations for a couple with infertility for 3 years, which is a rare event in human pathology. METHODS: Classical cytogenetics analysis, fluorescence in situ hybridization (FISH), and chromosome microarray analyses (CMA) were performed on peripheral blood lymphocytes; copy number variation sequencing (CNV-Seq) analysis was performed on sperm DNA. RESULTS: Classical cytogenetics analysis showed the presence of six cell lines on peripheral blood lymphocytes: 45, XY, der (13) t(13;22),-22[10]/46, XY, t(13;22)[6]/45, XY, der(15)t(15;22),-22[4]/46, XY, t(13;22)[1]/45, XY, der(5)t(5;22),-22[1]/45, XY, der(6)t(6;22)[1]. FISH and CMA performed on peripheral blood cells showed the presence of a 6.9 Mb mosaic 22q11 deletion (approximately 50% of cells); it is unexpected that the phenotypes of this man were merely oligoasthenozoospermia, mild bradycardia, and mild tricuspid regurgitation. CNV-Seq analysis performed on sperm DNA revealed the rate of 22q11 deletion cells was obviously lower compared with peripheral blood cells. And the frequency of gametes exhibiting a normal or balance chromosomal equipment was above 80% in sperm samples. CONCLUSION: To the best of our knowledge, this report is the first case of a de novo gonosomal mosaic of chromosome 22q11 deletion just associated with male infertility.

[Clinical manifestation and cytogenetic analysis of 607 patients with Turner syndrome].

OBJECTIVE: To explore the correlation between cytogenetic findings and clinical manifestations of Turner syndrome. METHODS: 607 cases of cytogenetically diagnosed Turner syndrome, including those with a major manifestation of Turner syndrome, were analyzed with conventional G-banding. Correlation between the karyotypes and clinical features were analyzed. RESULTS: Among the 607 cases, there were 154 cases with monosomy X (25.37%). Mosaicism monosomy X was found in 240 patients (39.54%), which included 194 (80.83%) with a low proportion of 45,X (3 ≤ the number of 45, X ≤5, while the normal cells ≥ 30). Structural X chromosome abnormalities were found in 173 patients (28.50%). A supernumerary marker chromosome was found in 40 cases (6.59%). Most patients with typical manifestations of Turner syndrome were under 11 years of age and whose karyotypes were mainly 45,X. The karyotype of patients between 11 and 18 years old was mainly 45,X, 46,X,i(X)(q10) and mos45,X/46,X,i(X)(q10), which all had primary amenorrhea in addition to the typical clinical manifestations. The karyotype of patients over 18 years of age were mainly mosaicism with a low proportion of 45,X, whom all had primary infertility. 53 patients had a history of pregnancy, which included 48 with non-structural abnormalities of X chromosome and 5 with abnormal structure of X chromosome. CONCLUSION: Generally, the higher proportion of cells with an abnormal karyotype, the more severe were the clinical symptoms and the earlier clinical recognition. Karyotyping analysis can provide guidance for the early diagnosis of Turner syndrome, especially those with a low proportion of 45,X.