Tools for Drawing Informative Idiograms

Each species has a typical karyotype, which represents the phenotypic appearance of the somatic chromosomes including number, size, and morphology. Idiogram is a diagrammatic representation of the chromosomes showing their relative size, homologous groups and different cytogenetic landmarks. Chromosomal analysis of cytological preparations is an essential component of many investigations which involves the calculation of karyotypic parameters and generation of idiogram. Although various tools are available for karyotype analysis, here we demonstrate karyotype analysis using our recently developed tool named KaryoMeasure. KaryoMeasure is a semi-automated free and user-friendly karyotype analysis software that facilitates data collection from different digital images of the metaphase chromosome spreads and calculates a wide variety of chromosomal and karyotypic parameters along with the related standard errors. KaryoMeasure draws idiograms of both diploid and allopolyploid species into a vector-based SVG or PDF image file.

Lessons from the Fukushima Daiichi nuclear power plant accident –from a research perspective

Since the accident at Fukushima Daiichi nuclear power plant, there has been a focus on the impact of low-dose radiation exposure due to nuclear disasters and radiology on human bodies. In order to study very low levels of impact on the human body from low-dose radiation exposure, a system with high detection sensitivity is needed. Until now, the most well-established biological radiation effect detection system in the field of emergency radiation medicine has been chromosomal analysis. However, chromosomal analysis requires advanced skills, and it is necessary to perform chromosomal analysis of a large number of cells in order to detect slight effects on the human body due to low-dose radiation exposure. Therefore, in order to study the effects of low-dose radiation exposure on the human body, it is necessary to develop high-throughput chromosome analysis technology. We have established the PNA-FISH method, which is a fluorescence in-situ hybridisation method using a PNA probe, as a high-throughput chromosome analysis technique. Using this method, the detection of dicentrics and ring chromosomes has become very efficient. Using this technology, chromosomal analysis was performed on peripheral blood before and after computed tomography (CT) examination of patients at Hiroshima University Hospital, and it was possible to detect chromosomal abnormalities due to low-dose radiation exposure in the CT examination. Furthermore, it was shown that there may be individual differences in the increase in chromosomal abnormalities due to low-dose radiation exposure, suggesting the need to build a next-generation medical radiation exposure management system based on individual differences in radiation sensitivity. If techniques such as chromosomal analysis, which have been used for biological dose evaluation in emergency radiation medicine, can be used for general radiology, such as radiodiagnosis and treatment, that will be a contribution to radiology from an unprecedented angle. This article will discuss the clinical application of new biological dose evaluation methods that have been developed in the field of emergency radiation medicine.

Atypical Presentation of Goldenhar Syndrome

Introduction In 1952 Goldenhar described a case with triad of pre auricular tags, mandibular hypoplasia and ocular (epibulbar) dermoid and described the case as Goldenhar Syndrome. Case Report A case of Goldenhar Syndrome without ocular involvement is presented. Discussion Goldenhar syndrome is also known as oculoauriculovertebral dysplasia due to presence of additional vertebral anomalies. Exact etiology of this disease is not known. Most of the cases are sporadic, though autosomal recessive/dominant and multifactorial inheritance has also been suggested. Chromosomal analysis shows no abnormalities.

Amenorrhoea with XY karyotype postbone marrow transplant

A 17-year-old girl presented with secondary amenorrhoea. She developed normal age-appropriate secondary sexual characteristics and attained menarche at the age of 13 years. One year following her menarche, she was diagnosed with acute myeloid leukaemia and was treated with chemotherapy, total body radiation and bone marrow transplant with complete remission. The matched donor was her elder male sibling. Her evaluation for secondary amenorrhoea included full hormonal analysis and pelvic ultrasound scan. These suggested hypergonadotrophic hypogonadism with a normal uterus and ovaries. Peripheral leucocyte karyotype as part of routine hypogonadism workup was found to be 46 XY. The differential diagnosis of Swyer syndrome, which entails surgical removal of gonads due to the high risk of gonadoblastoma, was raised initially before reviewing the laboratory results of previous chromosomal analysis. Considering her medical history, the amenorrhoea was finally attributed to ovarian insufficiency due to chemotherapy and radiotherapy. The 46 XY karyotyping could be explained by the bone marrow transplant received from her donor brother. Hypogonadism causing amenorrhoea is commonly encountered after chemoradiotherapy. Pretreatment and post-treatment chromosomal analysis is essential in such cases. Karyotyping could be misleading especially if the patient suffered from graft-versus-host reaction post gender mismatched bone marrow transplant.