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The Mahadevpur (27°39′48″ N, 95°51′32″ E; Arunachal Pradesh, India) meteorite is a fall‐type, coarse‐grained rock consisting of a heterogeneous mixture of chondrules of varying types occurring in a matrix comprising mostly chondrule fragments. It was earlier classified as poorly shocked (S1, unshocked) ordinary chondrite (H4/5). The minerals observed in the Mahadevpur meteorite include olivine, orthopyroxene, clinopyroxene, albitic‐plagioclase, Fe‐Ni alloy and troilite with minor amounts of chromite and phosphate. Olivine and orthopyroxene are almost equilibrated. The textures and compositional features of minerals and chondrule margins indicate a limited degree of recrystallization. The equilibration temperature (700–800°C) for the Mahadevpur chondrite is consistent with the computed temperature (752–902°C) derived from the coexisting orthopyroxene‐clinopyroxene pairs. In the light of new evidences observed during the present study, such as olivine exhibiting undulose extinction and planar to sub‐planar fractures, olivine and orthopyroxene showing strong mosaicism, the shock‐melted plagioclase glasses, the presence of high‐pressure mineral phases and silicate darkening, the earlier proposed shock stage pronouncement has been modified to S4–S5 with supporting petrographic, sub‐microscopic and Raman spectroscopic data. This is the first comprehensive account of the Mahadevpur chondrite with an upgraded shock stage classification. [ABSTRACT FROM AUTHOR]

Background: Rett syndrome (RTT) is characterized by a normal perinatal period with a normal head size at birth followed by normal development for the first 6 months of life followed by gradual deceleration of head growth, loss of acquired purposeful hand skills, severe expressive and receptive language impairment, severe intellectual disability and gait and truncal apraxia/ ataxia. It is caused due to mutations in the MECP2 gene and follows an X-linked dominant mode of inheritance. It was observed exclusively in females and was believed to be lethal in males. In contrast to this belief, several males were identified with RTT upon genetic analysis, however, most males expired by the age of 2 years due to neonatal encephalopathy. The ones that survived beyond the age of 2 years, were attributed to the presence of an extra X chromosome (co-occurrence of Klinefelter and RTT) or the ones having mosaic cell lines. Only 11 males with somatic mosaicism are known till date.Case Presentation: This case reports an ultra-rare case of a male affected with RTT surviving beyond the age of 2 years due to post-zygotic de novo somatic mosaicism. He was identified with a known pathogenic variant c.538C > T (p.R180*), which to the best of our knowledge is exclusively seen in females and has never been reported in a male before.Conclusion: The present case is the first report of a mosaic male affected with RTT from India. The present report also carried out genotype-phenotype correlations across surviving mosaic males with RTT. We also postulate the effect of variant type, position along the gene and the variant allele fraction in different tissue types to be correlated with disease severity. [ABSTRACT FROM AUTHOR]

Effective nowcasting for thunderstorms has been a challenge to operational forecasters in Jharkhand, India as lightning strikes-related deaths are significantly high. Extrapolation of radar echoes is the very foundation of nowcasting. Multiple radar mosaic data are able to pick out the size, shape, intensity, speed and direction of movement of individual storms on a continuous basis. This makes it possible to determine the likely location of a moving storm by extrapolation. This article demonstrates a new approach of locationspecific nowcast and SMS (short message service)- based dissemination system for thunderstorm and lightning warning up to 3 h ahead over Jharkhand. There are three components of the system. First, identification of the initial development and tracking of thunder cells by mosaic composite reflectivity data from multiple radars. The future location of thunder cells, and their growth or dissipation in terms of radius is estimated by extrapolation using their past trends. Secondly, based on this forecast information, an SMS is generated by the web-based GIS portal of Jharkhand Space Applications Centre for the forecast location and sent to the concerned state officials and mobile service providers over that region. Finally, the warning SMS is sent to all the active mobile users over that region at that time. The system combining nowcasting and dissemination of warning directly to the likely affected people is expected to be more robust considering its effectiveness in the reduction of human casualty. [ABSTRACT FROM AUTHOR]

Amenorrhea is the absence of menstruation in women of reproductive age. Previous reports suggest that chromosomal abnormality is the second most common cause of amenorrhoea. Early referral for cytogenetic evaluation is recommended for the identification of underlying chromosomal aberrations in amenorrhoea patients. This was an observational study which was conducted in Vivekananda Institute of Medical sciences, Kolkata, during January 2013–December 2015. This study aims to estimate the frequency and types of chromosomal abnormalities in primary amenorrhoea (PA) patients in Eastern India and correlate their hormonal profile with chromosomal reports. Clinical features of 150 patients were recorded with clinical expertise. Peripheral venous blood was taken following informed consent, followed by karyotyping for chromosomal analysis. Results revealed 76.1% of PA with normal female karyotype (46, XX) and 23.9% with different abnormal karyotypes. Among the abnormal karyotype constituents, 50% numerical abnormalities, most frequent being Turner syndrome, pure (n = 12, 8%) and mosaic (n = 5, 3.3%). Three cases (2%) showed male (XY) karyotype. The other cases showed X structural abnormalities. This study emphasises the need for cytogenetic analysis as integral part of the diagnostic protocol in case of PA for precise identification of chromosomal abnormalities and for appropriate management and counselling of these patients. [ABSTRACT FROM PUBLISHER]

Phakomatosis pigmentovascularis (PPV) is characterized by the association of a vascular nevus with a pigmentary nevus and is divided into five subtypes. PPV type II or Happle's phakomatosis cesioflammea is the most common subtype comprising of nevus flammeus along with pigmentary nevus in the form of aberrant Mongolian spots, nevus of Ota or less frequently nevus of Ito. It is estimated that around 50% of patients with PPV have systemic involvement, most frequently involving the central nervous system and eye. Other associated features include vascular abnormalities such as Sturge-Weber syndrome, and klippel trenaunay syndrome (KTS), and cutaneous lesions such as nevus anemicus (most common), cafe'-au-lait macules, generalized vitiligo and congenital triangular alopecia (CTA). There are only four reports of PPV associated with CTA in literature, and only a single previous report with associated KTS and this association has not been reported previously from India. We describe a case of a 30-year-old male having phakomatosis pigmentovascularis type II along with klippel trenaunay syndrome and associated with congenital triangular alopecia. [ABSTRACT FROM AUTHOR]

Background: Nevi are proposed to reflect the mosaicism and thus generally follow the different archetypal patterns of mosaicism. Blaschko's lines are the most common pattern of mosaicism. There have been many attempts to elucidate the Blaschko's lines on face from the distributional patterns of different nevi, but studies that evaluated exclusively pigmentary nevi are sparse. Aims: This study attempted to evaluate the patterns followed by different pigmentary nevi on face and utilized this to elucidate the pattern of embryological pigmentation on face. Materials and Methods: Spatial parameters like shape, orientation, and distribution patterns of different flat pigmentary nevi on face were analyzed and graphically drawn on human facial diagram. This was compared with existing facial Blaschko's lines. All cases of palpable pigmented nevi like congenital and giant melanocytic nevi and nevus spilus were excluded. Results: A total of 68 cases of pigmentary nevi on face (male-39, female-29) were examined. The shape and distribution lines were found to have a close similarity with Blaschko's lines on face with distinct differences. Conclusions: The concept of facial embryonic pigmentary 'segment', 'unit' and existence of separate Blaschko's lines for facial pigmentary nevi is conceived. Some insight into the pathogenesis of Blaschko's lines is also proposed in this study. [ABSTRACT FROM AUTHOR]

Severe incidence of a mosaic disease was observed on summer squash (Cucurbita pepo), commonly called pepo, grown in Varanasi during June-September of Khariff season 2007. Symptoms observed were mosaic, puckering on the leaves, wartiness on fruits, general stunting of plants and low yield. PCR amplification with degenerate primers designed to target the conserved sequences of coat protein gene of whitefly transmitted geminiviruses showed ∼800 bp fragment in all symptomatic samples tested, indicating the association of a geminivirus with the disease. Nucleotide sequence analysis of the amplified fragment showed 99% identity with pumpkin isolate of squash leaf curl china virus (SLCCNV) from Lucknow. It showed 85-96.7% homology with other isolates of SLCCNV from India and abroad. Phylogenetic analysis revealed the isolate on pepo from Varanasi clustered with SLCCNV isolates on pumpkin from Lucknow and Coimbatore. [ABSTRACT FROM AUTHOR]

Focal dermal hypoplasia is a rare disorder inherited in an X-linked dominant pattern and is usually antenatally lethal in males. We report a surviving male with postzygotic de novo mutation p.E300* in exon 10 of PORCN gene with mosaicism, earlier reported in a female of Thai origin. This is the irst report of this mutation from the Indian subcontinent. [ABSTRACT FROM AUTHOR]

Meiotic investigations were carried out in four different accessions of Balanites aegyptiaca (L.) Del. collected from various parts of Rajasthan, India. Chromosome associations, chiasma analysis and distinct pattern of chromosome/chromatids at anaphase I and II were studied in detail. The study revealed that all the accessions had the gametic chromosome number, except one (B. aegyptiaca BSJO-25160) that had n = 18. BSJO-25160 accession was characteristic in exhibiting chimeric nature as revealed through chromosome mosaicism, which resulted in variant chromosome number ranging from n = 9 to n = 16 in different pollen mother cells analyzed. The evolutionary implications of chromosome mosaicism/chimerism and its role in the development of anueploid series are discussed in detail. [ABSTRACT FROM AUTHOR]

During investigations of viroid diseases of food crops in Delhi, India, an infectious low- molecular-weight RNA (Mr 1.3 X 10^) was isolated from pigeonpea (Cajanus cajan) plants showing mosaic mottling and reduced size of leaves, stunting and no flowering. This RNA infected mechanically inoculated C. cajan, Chenopodium amaranticolor, Nicotiana glutinosa, and N. clevelandii. The causal agent, for which the name pigeonpea mosaic mottle viroid (PMMVd) is proposed, differed from N. glutinosa stunt viroid (NgSVd), the only viroid reported to infect legumes, in size and symptom expression on the original host species. [ABSTRACT FROM AUTHOR]

We present a case of a ring (21) in a mentally challenged patient with mosaicism for trisomy 21 showing karyotype 47, XY,+21/47,XY,+21(r)/46,XY, born to normal parents. The parents and female sibling were phenotypically normal. This is a unique case report from Central India, on occurrence of trisomy 21 and r (21) in the same individual born to normal parents. Also being documented for the first time is the immuno-FISH analysis revealing differential expression of hTERT and a linked over expression of TRF2 in proband, probably corresponding to a high percentage of acrocentric associations., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Pallister-Killian syndrome (PKS; OMIM: # 601803) is a rare sporadic genetic disorder characterized by pigmentary skin changes, distinctive dysmorphology, developmental delay, and mosaicism for tetrasomy of chromosome 12p. The authors report a case of PKS in a 2-y-old boy. He had pigmentary skin changes, characteristic facial features, developmental delay and hearing loss. He had sacral and post-auricular pits in addition, which has not yet been reported. A diagnosis of PKS was suspected on the basis of the patient's clinical features. Skin fibroblast culture was done which showed mosaic tetrasomy of isochromosome 12p consistent with Pallister-Killian syndrome. This case highlights the importance of dysmorphology as a diagnostic tool for recognition and accurate genetic counseling in genetic syndromes.

Chromosomal breakage investigation using diepoxybutane induction was carried out in 195 pediatric patients suspected with Fanconi anemia (FA). Chromosomal breakage evaluation showed 33 (17%) patients with classical FA, 9 (4%) with somatic mosaicism FA, (when at least 50% of the metaphases showed chromosomal breakage and radial figures), 25 (13%) with FA with high frequency of chromosomal breakage and without clinical features, and 128 (66%) with suspected FA but had no chromosomal breakage and clinical features of FA. Chromosomal breakage investigation is an important diagnostic tool for differentiating FA from idiopathic aplastic anemia.

The queenless ponerine ant Diacamma ceylonense and a population of Diacamma from the Nilgiri hills which we refer to as 'nilgiri', exhibit interesting similarities as well as dissimilarities. Molecular phylogenetic study of these morphologically almost similar taxa has shown that D. ceylonense is closely related to 'nilgiri' and indicates that 'nilgiri' is a recent diversion in the Diacamma phylogenetic tree. However, there is a striking behavioural difference in the way reproductive monopoly is maintained by the respective gamergates (mated egg laying workers), and there is evidence that they are genetically differentiated, suggesting a lack of gene flow. To develop a better understanding of the mechanism involved in speciation of Diacamma, we have analysed karyotypes of D. ceylonense and 'nilgiri'. In both, we found surprising inter-individual and intra-individual karyotypic mosaicism. The observed numerical variability, both at intra-individual and inter-individual levels, does not appear to have hampered the sustainability of the chromosomal diversity in each population under study. Since the related D. indicum displays no such intra-individual or inter-individual variability whatsoever under identical experimental conditions, these results are unlikely to be artifacts. Although no known mechanisms can account for the observed karyotypic variability of this nature, we believe that the present findings on the ants under study would provide opportunities for exciting new discoveries concerning the origin, maintenance and significance of intra-individual and inter-individual karyotypic mosaicism.

Background: Ring chromosome 7 [r(7)] is a rare cytogenetic aberration, with only 16 cases (including 3 females) reported in the literature to date. This is the first reported case of r(7) from India., Method: Clinical and cytogenetic investigations were carried out in an adult female with microcephaly and intellectual disability., Results: Ring chromosome 7 was observed in 10% of the metaphases (46,XX,r(7)/46,XX). The clinical findings revealed microcephaly, growth delay, and dark pigmented naevi., Conclusion: The mosaicism for a chromosomal anomaly is an under-recognised cause of intellectual disability.

Background: Hemophilia A is a common hereditary bleeding disorder caused mainly by mutations in the Factor VIII (FVIII) gene, which results in defective or absent FVIII protein. Most of the causative mutations arise from the germ cells, which leads to either heterozygous or hemizygous state for the mutation in the next generation. Germline or somatic mosaic may result due to a de novo mutation during early embryogenesis., Method: We analyzed 14 families of Indian origin with Hemophilia A [sporadic and severe] for the presence of mosaic individuals by employing Allele Specific PCR, mutation enrichment experiment and sequencing., Result: Nine families had point mutations, 3 families had small deletions or insertions, 2 families had splice site mutations. The origin of the de novo mutation was assigned to the patients' mother in 8 families. For 4 families it was assigned to the maternal grandmother and to the maternal grandfather in 2 families. In a single family somatic mosaic was detected., Conclusion: The presence of somatic mosaic in families with sporadic Hemophilia A in India may confound risk estimation during genetic counseling.

We have characterized near full-length genomes of three B/C recombinants of HIV-1 from the northeastern state of India. The recombinant viruses showed a backbone of subtype C virus with a single insertion of the subtype B genome in the envelope region. While all of them were distinct from B/C recombinants CRF_07 and CRF_08 circulating in China and CRF_04BR137 circulating in Brazil, two of them presented with break-points identical to the Argentinean B/C recombinant ARE195FL. However, neighbor-joining analysis followed by phylogenetic clustering showed that gp120 belonging to subtype B of all the recombinants clustered with Thai B sequences, while subtype C gag clustered with an Indian subtype C sequence, suggesting a unique ancestral origin of these recombinants.

We analysed chromosomes, conducted hormonal assays and screened genomic DNA of 34 patients with or without detectable Y chromosome for the presence/absence of SRY, PABY, DYS1, DYZ3 and DYZ1 loci and for mutations in the SRY gene. The samples studied represented cases of oligozoospermia, cryptorchidism, Swyer syndrome, Turner syndrome, male pseudohermaphroditism, XXY female syndrome, Klinefelter's syndrome, repeated abortion and instances of male infertility. Chromosomal constitutions and the level of hormones (FSH, LH, PRL, E2 and TSH) were found to be abnormal in several cases. A phenotypic female (P20) positive for all the Y-linked loci screened, showed mutations upstream of the HMG box in the SRY gene. In addition, one or more of the Y-linked loci were detected in several phenotypic females. Fluorescence in-situ hybridization of metaphase chromosomes and interphase nuclei of an aborted fetus with DYZ1 probe detected signals from normal to low levels to its complete absence confirming a complex Y chromosome mosaicism. Upon DNA analysis, the fetus was found to be positive for all the above-mentioned Y-linked loci. Organizational variation within the DYZ1 arrays and its correlation with recurrent spontaneous abortion may be followed-up in subsequent studies to substantiate this observation. This would augment genetic counselling to the affected couples. Prospects of this approach in the overall management of clinical cases with sex chromosome-related anomalies are discussed.

Fragile-X-linked mental retardation usually results from amplification of the CGG repeat in the 5' untranslated region of the FMR1 gene. To assess the extent of variation of the CGG repeat in the population from the eastern region of India we studied 98 mentally retarded individuals living in and around Calcutta and identified 21 distinct alleles ranging in size from 8 to 44 CGG repeats. A repeat size of 28 was the most frequent; this value is different from the most frequent repeat size found in other studies, indicating a racial or ethnic variation. Patients with the clinical features of the syndrome have been found to carry expanded CGG repeats. Thus, it can be inferred that the expansion of CGG repeats may be a frequent cause of the syndrome in our population.

We present a report of the parental ages (n = 865) and parental origin of meiotic nondisjunction (n = 236) that are likely to show a predisposition in the etiology of Down syndrome (DS). Chromosomal analysis, performed over a 20-year period, on 1,001 Down syndrome subjects, revealed pure trisomy 21 karyotype in 880 subjects (87.92%), mosaic trisomy karyotype in 77 (7.69%), and translocation karyotype in 44 (4.39%). The mean maternal age was found to be 30.34 years, and mean paternal age was 31.04 years. Nondisjunctional error was 79.24% maternal and 20.76% paternal. The findings of the study revealed the significant contribution of advanced parental age and increased maternal meiotic nondisjunctional error to the origin of trisomy 21 Down syndrome.

A cytogenetic analysis of Down's syndrome revealed straight trisomy 21 in 96.5 per cent affected. Remaining 3.5 per cent were found to have chromosomal mosaicism. In addition, a normal karyotype was observed in 2 individuals with Down's phenotype. A survey of Down's syndrome in Hyderabad gave an incidence of 1.17 per 1000 or 1 in 853 live births. There was a significant increase in the mean maternal age of the affected over the controls. Sex ratio was also higher in our sample of Down's syndrome as compared to the general population.