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b) Environmental factors
 
b) Environmental factors
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c)Idiopathic(unknown) factors.  
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c)Idiopathic(unknown) factors.<ref>https://embryology.med.unsw.edu.au/embryology/index.php/Abnormal_Development.</ref>
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The genetic factors are related to maternal and paternal age, family history, ethnic background etc.  
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The genetic factors are related to maternal and paternal age, family history, ethnic background etc.<ref>https://embryology.med.unsw.edu.au/embryology/index.php/Abnormal_Development_-_Genetic</ref>
 
    
 
    
Environmental factors includes maternal infections (Eg-TORCH infection), maternal diet (eg- folic acid deficiency leading to neural tube defects), life style (adverse effects of smoking, alcoholism etc.) and certain drugs or chemicals(teratogenic effect).The environmental factors that cause or lead to any of the abnormalities are described as teratogens.  
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Environmental factors includes maternal infections (Eg-TORCH infection), maternal diet (eg- folic acid deficiency leading to neural tube defects), life style (adverse effects of smoking, alcoholism etc.) and certain drugs or chemicals(teratogenic effect).The environmental factors that cause or lead to any of the abnormalities are described as teratogens.<ref>https://embryology.med.unsw.edu.au/embryology/index.php/Human_Abnormal_Development#Environmental</ref>
    
Prenatal diagnosis are the clinical tools used to determine both normal and abnormal development.Many diagnostic techniques are being applied to diagnose human embryonic development.
 
Prenatal diagnosis are the clinical tools used to determine both normal and abnormal development.Many diagnostic techniques are being applied to diagnose human embryonic development.
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The two major classes of techniques are invasive and non-invasive testing.  
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The two major classes of techniques are invasive and non-invasive testing.<ref>https://embryology.med.unsw.edu.au/embryology/index.php/Prenatal_Diagnosis</ref>
    
A Combined first trimester screening test (cFTS) involves a maternal ultrasound scan and blood tests at 11-13weeks of pregnancy. Genetic screening includes maternal serum alpha-fetoprotein (MSAFP), triple test at 15-18 weeks for mother at risk of carrying a fetus with neural tube defects, down syndrome or another chromosomal anomaly.
 
A Combined first trimester screening test (cFTS) involves a maternal ultrasound scan and blood tests at 11-13weeks of pregnancy. Genetic screening includes maternal serum alpha-fetoprotein (MSAFP), triple test at 15-18 weeks for mother at risk of carrying a fetus with neural tube defects, down syndrome or another chromosomal anomaly.
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==Current researches ==
 
==Current researches ==
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*During early embryogenesis, the pro-embryo consists of two domains, the embryo proper and the suspensor. Recent studies have revealed that the suspensor plays an important role in early embryogenesis and the process of suspensor formation and degeneration may provide a unique model for studies on cell division pattern, cell fate determination, and cell death.  The different shapes attributed to the early embryonic development like jelly mass, knot like structure, elongated muscle like structure, irregular elevation etc. described in Ayurveda embryology may be explored on the basis of these findings.
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*During early embryogenesis, the pro-embryo consists of two domains, the embryo proper and the suspensor. Recent studies have revealed that the suspensor plays an important role in early embryogenesis and the process of suspensor formation and degeneration may provide a unique model for studies on cell division pattern, cell fate determination, and cell death.<ref>Peng X, Sun MX. The suspensor as a model system to study the mechanism of cell fate specification during early embryogenesis. Plant Reprod. 2018;31(1):59‐65. doi:10.1007/s00497-018-0326-5</ref> The different shapes attributed to the early embryonic development like jelly mass, knot like structure, elongated muscle like structure, irregular elevation etc. described in Ayurveda embryology may be explored on the basis of these findings.
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*Precise gene expression ensures proper stem and progenitor cell differentiation, lineage commitment and organogenesis during mammalian development. ATP-dependent chromatin-remodeling complexes utilize the energy from ATP hydrolysis to reorganize chromatin and, hence, regulate gene expression. These complexes contain diverse subunits that together provide a multitude of functions, from early embryogenesis through cell differentiation and development into various adult tissues.  These cell differentiation processes are mainly attributed to the action of [[vata]] [[dosha]].
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*Precise gene expression ensures proper stem and progenitor cell differentiation, lineage commitment and organogenesis during mammalian development. ATP-dependent chromatin-remodeling complexes utilize the energy from ATP hydrolysis to reorganize chromatin and, hence, regulate gene expression. These complexes contain diverse subunits that together provide a multitude of functions, from early embryogenesis through cell differentiation and development into various adult tissues.<ref>Hota SK, Bruneau BG. ATP-dependent chromatin remodeling during mammalian development. Development. 2016;143(16):2882‐2897. doi:10.1242/dev.128892.</ref> These cell differentiation processes are mainly attributed to the action of [[vata]] [[dosha]].
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*The maternal-to-embryonic transition consists of critical developmental processes including maternal RNA depletion and embryonic genome activation. In recent years, key maternal proteins encoded by maternal-effect genes have been determined, primarily using genetically modified mouse models. These proteins are implicated in various aspects of early embryonic development including maternal mRNA degradation, epigenetic reprogramming, signal transduction, protein translation and initiation of embryonic genome activation.These shows the importance and main contribution of maternal factor (matruja bhava) in the early stage of embryonic development. Diseases that occur due to mutation in the mitochondrial genome are inherited only from the mother, as only the ovum contains mitochondrial genetic material.  
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*The maternal-to-embryonic transition consists of critical developmental processes including maternal RNA depletion and embryonic genome activation. In recent years, key maternal proteins encoded by maternal-effect genes have been determined, primarily using genetically modified mouse models. These proteins are implicated in various aspects of early embryonic development including maternal mRNA degradation, epigenetic reprogramming, signal transduction, protein translation and initiation of embryonic genome activation.<ref>Zhang K, Smith GW. Maternal control of early embryogenesis in mammals. Reprod Fertil Dev. 2015;27(6):880‐896. doi:10.1071/RD14441</ref>These shows the importance and main contribution of maternal factor (matruja bhava) in the early stage of embryonic development. Diseases that occur due to mutation in the mitochondrial genome are inherited only from the mother, as only the ovum contains mitochondrial genetic material.<ref>Dhiman K, Kumar A, Dhiman KS. Shad Garbhakara Bhavas vis-a-vis congenital and genetic disorders. Ayu. 2010;31(2):175-184. doi:10.4103/0974-8520.72384</ref>
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*Advanced paternal age is well-documented to be associated with new dominant mutations and paternal exposures to drugs may increase the risk of adverse fetal outcome.  
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*Advanced paternal age is well-documented to be associated with new dominant mutations and paternal exposures to drugs may increase the risk of adverse fetal outcome.<ref>Robaire B, Hales BF. The male germ cell as a target for drug and toxicantaction. In: Gagnon C, ed. The Male Gamete: From Basic Science to Clinical Applications. Boca Raton, Fla: Cache River Press; 1999:469-74</ref>, <ref>Savitz. Paternal Exposure to Drugs Reviewand Environmental Chemicals: Effects onProgeny Outcome Journal of Andrology, Vol. 22, No. 6,page no- 930 November/December 2001- American Society of Andrology</ref>
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*Epigenetic mechanisms are influenced by several factors like development in utero and in childhood, environmental chemicals, drugs and pharmaceuticals, aging, and diet. Example- Methyl groups, an epigenetic factor found in some dietary sources, can tag DNA and activate or repress genes which is known as DNA methylation. So, the six procreative factors (Shad garbhakara bhava) have an important role as causative factors of congenital, hereditary, and genetic anomalies by mutation and epigenetics.  
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*Epigenetic mechanisms are influenced by several factors like development in utero and in childhood, environmental chemicals, drugs and pharmaceuticals, aging, and diet. Example- Methyl groups, an epigenetic factor found in some dietary sources, can tag DNA and activate or repress genes which is known as DNA methylation. So, the six procreative factors (Shad garbhakara bhava) have an important role as causative factors of congenital, hereditary, and genetic anomalies by mutation and epigenetics.<ref>Dhiman K, Kumar A, Dhiman KS. Shad Garbhakara Bhavas vis-a-vis congenital and genetic disorders. Ayu. 2010;31(2):175-184. doi:10.4103/0974-8520.72384</ref>
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*Designer babies are babies from embryos formed by in-vitro fertilization (IVF). They are either created from an embryo selected by preimplantation genetic diagnosis (PGD) or genetically modified in order to influence the traits of the resulting children. The primary aim of creating designer babies is to avoid heritable diseases coded by mutations in DNA.
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*Designer babies are babies from embryos formed by in-vitro fertilization (IVF). They are either created from an embryo selected by preimplantation genetic diagnosis (PGD) or genetically modified in order to influence the traits of the resulting children. The primary aim of creating designer babies is to avoid heritable diseases coded by mutations in DNA.<ref>Ronald T.K. Pang, P.C. Ho,Designer babies,Obstetrics, Gynaecology & Reproductive Medicine,Volume 26, Issue 2,2016,Pages 59-60,ISSN 1751-7214,https://doi.org/10.1016/j.ogrm.2015.11.011</ref>
    
==More information ==
 
==More information ==
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