Exploration of clinical and genetic findings in Ataxia-Telangiectasia (AT) patients from the Indian subcontinent

BACKGROUND

Ataxia-Telangiectasia (AT) is a rare autosomal recessive neurodegenerative disorder. It is caused by mutations in the Ataxia-Telangiectasia mutated (ATM) gene, which codes for protein ATM serine/threonine kinase.

OBJECTIVE

We aim to describe the clinical and radiological findings in children and adolescents of 20 molecularly confirmed cases of AT. We aim to correlate these findings with the genotype identified among them.

METHODS

This retrospective study included 20 patients diagnosed clinically and genetically with AT over 10 years. The clinical, radiological and laboratory data were extracted from the hospital's electronic medical records. Molecular testing was done using next generation sequencing and Sanger sequencing. In silico predictions were performed for the variants identified by applying Cryp-Skip, Splice site prediction by Neural Network, Mutation Taster and Hope prediction tool.

RESULTS

Consanguinity was documented in nearly half of the patients. Telangiectasia was absent in 10%. Microcephaly was seen in 40% cases. The incidence of malignancy in our study population was low. Molecular testing done in the 18 families (20 patients) identified 23 variants of which ten were novel. Biallelic homozygous variants were noted in 13 families and compound heterozygous in 5 families. Out of the 13 families who were homozygous, 8 families (61.5%) (9 patients) have history of consanguinity. In silico prediction of novel missense variants, NM_000051.4 (ATM_v201): c.2702T > C showed disruption of the α-helix of ATM protein and NM_000051.4 (ATM_v201): c.6679C > G is expected to disturb the rigidity of protein structure in the FAT domain. The four novel splice site variants and two intronic variants result in exon skipping as predicted by Cryp-Skip.

CONCLUSIONS

AT should be confirmed by molecular testing in young-onset cerebellar ataxia, even without telangiectasia. Awareness of this rare disease will facilitate study of larger cohorts from Indian population to characterize variants and determine its prevalence in this population.

Cerebrotendinous Xanthomatosis: Report of Two Siblings With the Same Mutation but Variable Presentation

Cerebrotendinous xanthomatosis (CTX), also known as CTX, is an extremely rare bile acid metabolic disorder caused by mutations in the cytochrome P450 family 27 subfamily A member 1 (CYP27A1) gene. This genetic disease is inherited in an autosomal recessive manner, and it affects the enzyme sterol 27-hydroxylase, which is involved in the bile acid metabolic process. It is distinguished by diarrhoea in infancy, early juvenile cataract, tendon xanthomas in adolescence, and progressive neuropsychiatric dysfunction in adulthood. So far, India has reported eight genetically confirmed cases. We present two cases of CTX among siblings in a family. The elder sibling was initially diagnosed, and after reviewing his family history and performing a thorough clinical examination, we discovered a similar manifestation in his younger sibling. Genetic testing on the siblings revealed similar mutations at exon 2 of the CYP27A1 gene. If a pathogenic mutation is discovered in a family member, prenatal and preimplantation genetic testing, as well as childhood screening, are the options. These screening strategies will prevent the onset of neuropsychiatric manifestations and disability.

Novel Mutations in CRLF1: Case Reports with Crisponi Syndrome

Crisponi syndrome (CS) is a rare autosomal recessive syndrome, characterized by episodic facial muscle contraction with trismus, abundant salivation along with intermittent hyperthermia, feeding difficulties, characteristic facial dysmorphism, and camptodactyly. Here the authors report two South Indian neonates with confirmed diagnosis of Crisponi syndrome, caused by novel pathogenic variants in cytokine receptor-like factor 1 (CRLF1) gene. The classical clinical findings observed in the present cases were feeding difficulty, facial dysmorphism, tachypnea, contractures, camptodactyly, opisthotonus, hyperthermia, poor growth, and facial muscle contraction resembling probable tetanus. The patients with variants identified in the signal peptide domain had typical spasms from day one of life as compared to the variants in other domains who had later onset at neonatal period. The authors provide a review of the cases described, so far, from India highlighting that no common variants attribute to this rare syndrome. Recognizing this syndrome is crucial to differentiate it from infective conditions and for effective genetic counseling. Though tetanus is almost eradicated in developing countries, genetic causes should be suspected in new cases.

Household waste reduction efficiency of Hermetia illucens larvae

Waste management with limited resource input under minimum space is the need of the hour. Black Soldier Fly (BSF)/Hermetia illucens is a fly prevailing and flourishing in our tropical climatic condition and is a miracle insect since it can solve a multitude of global problems like waste management, animal feed production and energy production. This fly is highly reputed in converting low quality biomasses in to high protein, high energy larvae meal. In this study we are assessing the quantity of BSF larvae produced from food waste and the waste reduction efficiency of the BSF larvae. Four kilograms of food waste was kept in a modified bin with 6 replicates and the development of the larvae was through natural breeding. The study revealed that from the above said quantity, an average of 0.567kg of BSF larvae can be produced per bin and average waste reduction efficiency was 73.81%.

Malignant Melanoma and Filariasis: A Coexistence or an Association?

Malignancy has been reported with chronic lymphedema, especially lymphangiosarcoma. The authors report on a patient with lymphedema due to filariasis, presenting with an ulcerated pigmented lesion that was malignant melanoma. A literature search revealed no previous report of such lesions existing together.

Plant defense response against Fusarium oxysporum and strategies to develop tolerant genotypes in banana

Soil-borne fungal pathogen, Fusarium oxysporum causes major economic losses by inducing necrosis and wilting symptoms in many crop plants. Management of fusarium wilt is achieved mainly by the use of chemical fungicides which affect the soil health and their efficiency is often limited by pathogenic variability. Hence understanding the nature of interaction between pathogen and host may help to select and improve better cultivars. Current research evidences highlight the role of oxidative burst and antioxidant enzymes indicating that ROS act as an important signaling molecule in banana defense response against Fusarium oxysporum f.sp. cubense. The role of jasmonic acid signaling in plant defense against necrotrophic pathogens is well recognized. But recent studies show that the role of salicylic acid is complex and ambiguous against necrotrophic pathogens like Fusarium oxysporum, leading to many intriguing questions about its relationship between other signaling compounds. In case of banana, a major challenge is to identify specific receptors for effector proteins like SIX proteins and also the components of various signal transduction pathways. Significant progress has been made to uncover the role of defense genes but is limited to only model plants such as Arabidopsis and tomato. Keeping this in view, we review the host response, pathogen diversity, current understanding of biochemical and molecular changes that occur during host and pathogen interaction. Developing resistant cultivars through mutation, breeding, transgenic and cisgenic approaches have been discussed. This would help us to understand host defenses against Fusarium oxysporum and to formulate strategies to develop tolerant cultivars.

Sciatic nerve schwannoma

Schwannomas are benign tumors of the nerve sheath, commonly seen in the vestibular nerve. Although they are common in the head and neck areas, their occurrence in extra-cranial locations is rare. We report a case of a sciatic nerve schwannoma and review the literature.

Chronic lower limb ulcer? No--chloroma!

Extra medullary deposits are often associated with myeloproliferative disorders, especially with myeloid neoplasia. These are called granulocytic sarcoma, aleukemic leukemia cutis, myeloblastoma, chloroleukemia, extra-medullary myeloid tumor, and chloroma. They commonly present in the bone, periosteum, soft tissue, lymph nodes, and the skin but can occur anywhere. The authors present their experience with a patient with no history of neoplasm presented with a nonhealing ulcer of the lower limb that was a chloroma associated with chronic myeloid leukemia.

An uncommon sighting--lupus vulgaris of the foot

Lupus vulgaris (LV)is a progressive form of cutaneous tuberculosis (TB)that may occur in a patient with a moderate or high degree of immunity. The incidence of LV has declined with that in TB; it is relatively uncommon even in developing countries. LV commonly presents in the head and neck regions as flat plaques. Variants of LV form huge, soft, tumor-like forms with deep tissue and cartilage destruction resulting in deformities. The authors report a case of LV in a patient who presented with an ulcero-proliferative growth in the lower extremity, mimicking a malignancy.

Extra-Articular Pigmented Villonodular Synovitis

Villonodular synovitis are a group of idiopathic lesions that affect the synovial surfaces of joints, tendon sheaths, and bursae, causing tumor-like lesions. Pigmented villonodular synovitis rarely affects the tendon sheaths; its occurrence in extra-articular sites is uncommon. This case is presented for the rarity of occurrence. The literature is also reviewed.