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Primordial dwarfism is a group of genetic disorders which include Seckel Syndrome, Silver-Russell Syndrome, Microcephalic Osteodysplastic Primordial Dwarfism types I/III, II and Meier-Gorlin Syndrome. This genetic disorder group is characterized by intra-uterine growth retardation and post-natal growth abnormalities which occur as a result of disorganized molecular and genomic changes in embryonic stage and, thus, it represents a unique area to study growth and developmental abnormalities. Lot of research has been carried out on different aspects; however, a consolidated review that discusses an overall spectrum of this disorder is not accessible. Recent research in this area points toward important molecular and cellular mechanisms in human body that regulate the complexity of growth process. Studies have emerged that have clearly associated with a number of abnormal chromosomal, genetic and epigenetic alterations that can predispose an embryo to develop PD-associated developmental defects. Finding and associating such fundamental changes to its subtypes will help in re-examination of alleged functions at both cellular and developmental levels and thus reveal the intrinsic mechanism that leads to a balanced growth. Although such findings have unraveled a subtle understanding of growth process, we further require active research in terms of identification of reliable biomarkers for different subtypes as an immediate requirement for clinical utilization. It is hoped that further study will advance the understanding of basic mechanisms regulating growth relevant to human health. Therefore, this review has been written with an aim to present an overview of chromosomal, molecular and epigenetic modifications reported to be associated with different subtypes of this heterogenous disorder. Further, latest findings with respect to clinical and molecular genetics research have been summarized to aid the medical fraternity in their clinical utility, for diagnosing disorders where there are overlapping physical attributes and simultaneously inform about the latest developments in PD biology.

TP53 is a tumor suppressor gene which is commonly mutated in various cancers including breast cancer. Alterations in the gene lead to an altered expression of various genes that are directly or indirectly under the transcriptional control of p53. This results in malfunctioning of DNA damage repair pathways, cell-cycle arrest, chromatin remodeling and apoptosis. Different mutations in TP53 gene have been reported in different ethnic groups and exon 4 and intron 3 are reported to be frequently mutated in breast cancer patients especially triplenegative breast cancer. Increased global burden of TP53 mutated breast tumors has paved the path for various therapies targeting p53/TP53. Numerous molecules including nutilins, MI series, RO5693, PRIMA-1, RITA, etc. have been developed. Majority of these restore p53/TP53 function by targeting negative regulators of p53/TP53, wtp53/TP53 (wild-type) and mtp53/TP53 (mutant). Most of these molecules are in the preclinical phase except for two APR-246 and COTI-2 that have progressed to clinical trials. The current review has been compiled with an aim to give an overview of mutations in p53 across various ethnic groups, the effect of these alterations on TP53 function and the therapeutic strategies developed till date targeting p53/TP53 especially in breast cancer.

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