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Chromosome karyotyping analysis plays a crucial role in prenatal diagnosis for diagnosing whether a fetus has severe defects or genetic diseases. However, due to the complicated morphological characteristics of various types of chromosome clusters, chromosome instance segmentation is the most challenging stage of chromosome karyotyping analysis, leading chromosome karyotyping analysis to highly dependent on skilled clinical analysts. Since most of the chromosome instance segmentation efforts are currently devoted to segmenting chromosome instances from different types of chromosome clusters, type identification of chromosome clusters is a vital anterior task for chromosome instance segmentation. Firstly, this paper proposes an automatic approach for chromosome cluster identification using recent transfer learning techniques. The proposed framework is based on ResNeXt weakly-supervised learning (WSL) pre-trained backbone and a task-specific network header. Secondly, this paper proposes a fast training methodology that tunes our framework from coarse-to-fine gradually. Extensive evaluations on a clinical dataset consisting of 6592 clinical chromosome samples show that the proposed framework achieves 94.09%accuracy, 92.79%sensitivity, and 98.03%specificity. Such performance is superior to the best baseline model that we obtain 92.17%accuracy, 89.1%sensitivity, and 97.42%specificity. To foster research and application in the chromosome cluster type identification, we make our clinical dataset and code available via GitHub.

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OBJECTIVE: This study aimed to establish a new external quality assessment (EQA) of chromosomal karyotype analysis. METHODS: Chimeric assembly A1 was established by collecting chimeric chromosome images prepared artificially from chromosomally abnormal amniocytes remaining after prenatal diagnosis. Chimeric assembly B1 and nonchimeric assembly C1 were constructed through the collection of chimeric and nonchimeric chromosome images from prenatal diagnosis, respectively. Then, chromosome images were selected randomly from assemblies A1, B1, or C1 to send to 20 technicians via email to verify the validity of a new EQA of chromosomal karyotype analysis. RESULTS: According to the EQA of 20 technicians, 47,XX,+mar from assembly A was easily misdiagnosed as 47,XX,+19 or 47,XXY, and 45,XX,t(13;22) (q10;q10) was misdiagnosed as 45,XX,13S+,-22. The total misdiagnosis rate was 3.8%. For assembly B, 46,X,+mar and 46,X,idic(Y) were easily misdiagnosed as 46,XY and 46,X,+mar, respectively. In addition, some testers missed 47,XXX in 47,XXX[2]/46,XX[48], as well as 47,XX,+18 in 46,XX [47]/47,XX,+18[3], and 45,X and 47,XXX in 46,XX[47]/45,X[2]/47,XXX[1]. The total misdiagnosis rate was 4.2%. All karyo-types from assembly C were correctly diagnosed, although incorrect descriptions used for 4% of cases. CONCLUSION: The quality of chromosome karyotype analysis can be comprehensively evaluated by a new EQA based on assembly A1 or B1.

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OBJECTIVE: The pericentric inversion of chromosome 9 (inv9) is one of the most common structural balanced chromosomal variations, and it is considered to be a normal population variant. The aim of this study was to re-evaluate the clinical impact of patients with inv9. METHODS: We studied the karyotypes from 4853 patients at a single center and retrospectively reviewed their clinical data. RESULTS: There were 67 inv9 patients among 2988 adults, and 62 of them showed different clinical features, including male and female infertility, oligoasthenozoospermia, and azoospermia. Thirty-one cases of inv9 were found in 1865 fetuses, including two cases in chorionic villus (6.90%) and 29 in amniotic fluid (1.67%), but there were no cases in umbilical cord blood. The rates of fetal phenotype abnormal and adverse pregnancy outcome with inv9 in the chorionic villus were 100.00% (2/2), while only 17.24% (5/29) in the amniotic fluid showed abnormalities, among which 60.00% (3/5) had adverse pregnancy outcomes. CONCLUSIONS: Although there is no clear evidence that inv9 is pathogenic, the genetic counseling on inv9 in early pregnancy and adults needs to be given more attention.

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OBJECTIVE: Genetic defects and endocrine-related factors are the leading causes of male infertility. This study was performed to analyze the genetic characteristics and sex hormone levels in different types of male infertility. METHODS: A total of 423 men with infertility underwent genetic and sex hormone analysis at The Sixth Affiliated Hospital of Guangzhou Medical University. RESULTS: The incidences of abnormal karyotypes in patients with male infertility, azoospermia, and oligoasthenozoospermia were 6.94%, 22.40%, 15.09%, respectively. Among men with azoospermia, Klinefelter syndrome (47,XXY) was identified in 60.71% (17/28) of those with abnormal karyotypes. Additionally, the levels of follicle-stimulating hormone and human luteinizing hormone were significantly higher in men with azoospermia showing abnormal karyotypes than in men of the other study groups. The serum testosterone level in men with azoospermia showing abnormal karyotypes was lower than that in men of the other study groups. CONCLUSIONS: Azoospermia is closely associated with chromosome abnormalities. The levels of testosterone, human luteinizing hormone, and follicle-stimulating hormone in men with azoospermia showing abnormal karyotypes provide a clinical reference for genetic counseling and assisted reproduction.

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Objective@#To report on a case of maternally derived 45, X mosaicism detected by non-invasive prenatal testing (NIPT).@*Methods@#Fetal sex chromosomal abnormality was detected by NIPT. Maternally derived 45, X mosaicism was confirmed by chromosome karyotype analysis. Fetal sex chromosome aneuploidy was detected by amniotic fluid chromosome microarray analysis.@*Results@#A maternal 45, X mosaicism was diagnosed. The fetus was confirmed to be normal.@*Conclusion@#Maternal 45, X masaicism can be diagnosed by NIPT.

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Objective To make the chromosome karyotype analysis of 130 patients with leukemia by using the improved chromosome short-term culture method.Methods We optimized the main factors with a single factor gradient experiment in short-term culture of bone marrow chromosome, including colchicines concentration, duration of action of colchicines,and hypotonic time.On this basis,we conducted the three-factors and three-level orthogonal experiment to achieve improved bone marrow chromosome preparation system,which was later applied in 130 patients with leukemia in our hospital.Results The orthogonal experiment results showed that the optimum conditions were colchicines concentration of 0.07 μg/mL,colchicines action time of 80 min,and hypotonic time of 35 min during the preparation of the bone marrow chromosome.Using this method,the chromosome preparation success rate reached 97.69% and the detection rate of abnormal karyotype reached 82.3% in the chromosome karyotype analysis.Conclusion Bone marrow chromosome preparation system with colchicines concentration of 0.07 μg/mL and colchicines action time of 80 min,and hypotonic time of 35 min is worthy of clinical promotion.

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Objective To explore the clinic value of chromosome karyotype analysis of amniotic fluid cells in prenatal diagnosis . Methods 1 466 cases of pregnant women who had the prenatal diagnosis indexes were selected ,and their amniotic fluid specimens were collected through amniocentesis guiding by type‐B ultrasonic around the 16th to 24th week .Amniotic fluid cells were gained after a successful cell culture .G banding was used for the karyotype analysis of amniotic fluid cells .Results The one‐time success rate of cultivation for amniotic fluid cells was 99 .8% .In 1 466 cases of pregnant women ,there were 16 cases of abnormal karyotype polymorphism (including 12 cases of trisomy 21 ,1 case of trisomy 18 ,and 3 cases of Chromosome abnormalities) and 3 cases of chromosomal polymorphism .Conclusion The chromosome karyotype analysis of amniotic fluid cell is still an irreplaceable test in prenatal diagnosis .