How does a cell become different from its parent cell? How do two identical daughter cells become different from one another? How might one daughter cell become a neuron, while the other daughter cell becomes a skin cell? A prakriti differentiation among individuals and siblings can aptly be defined through this primary cellular mechanism of cell differentiation. In some cases, determination results from the asymmetric segregation of cellular determinants. However, in most cases, determination is the result of inductive signaling between cells.

Asymmetric segregation of cellular determinants is based on the asymmetric localization of cytoplasmic molecules (usually proteins or mRNAs) within a cell before it divides. During cell division, one daughter cell receives most or all of the localized molecules, while the other daughter cell receives less (or none) of these molecules. This result in two different daughter cells, which then take on different cell fates based on differences in gene expression. The localized cytoplasmic determinants are often mRNAs encoding transcription factors, or the transcription factors themselves. Unequal segregation of cellular determinants is observed during early development of the C. elegans and Drosophila embryos. From Ayurvedic perspective proposing for a five elemental composition to every living cell, this could be the differential distribution of these formative elements among daughter cells leading to their differential fate through variable dosha activity resulting through the differential gene expression.

The prakriti is conceived to be decided at cell determination stage when this is no more changeable. Further to the determination, at the stage of differentiation, it is possibly the elemental predominance, which acts as the signal to differential expression of genes and hence making a path to the morphological and function differentiation of the cells. Without any convincing data to support with, panchamahabhuta theory of Ayurveda seems to operate at a level deeper than differential gene expressions. It tries to underline the various reasons, which may possibly act as the signals to make a cell differentiated. These signals can aptly be called as panchbhut in Ayurveda, and a prakriti may be proposed as a net characterization of determined cells, which are differentiated gradually to express them morphologically and functionally in course of their development.

Ayurveda prima-facie considers the maternal (matraja bhava), paternal (pitraja bhava) inheritance and maternal dietary influence (rasaj bhava) as responsible for distinctive features in every fetus [12]. These influencing factors with reference to the prakriti determination may act via signals which either operate through a differential elemental distribution or support to a particular element group. Ayurveda proposes an elemental predominance representation through the physical, physiological, and mental features attributed to the corresponding element [33]. Following is a summary of Ayurvedic perception of how panchabhuta are represented phenotypically in growing fetus and how they are responsible for bringing specific features to growing fetus (Table 7.2).

It is proposed that panchamahabhuta are responsible for the arousal of specific perceptions and corresponding sense organs in the body. Apart from physical specifications as softness, roughness, physical dimensions, toughness, and gross appearance, they are also responsible for some specific physiological and mental functions.

Because of its invasion into almost every theoretical and practical aspect of Ayurveda, prakriti fundamentally and dosha as its applied extension, presented themselves as the central dogma of Ayurveda. Fascinated by its possible application to Ayurvedic diagnostics and for its being as an evidence to help decision making for personalized treatment, it has recently evoked the scientific community to look at the issue in their own perspectives [9]. It was vividly approached to see if the prakriti has a genomic basis [12, 35]. In a meticulous approach to quantify tridosha through biostatistical methods, Joshi [7] succeeded to conclude that tridosha has a concrete empirical basis which can be utilized for its scientific establishment. Inspired by the initial findings of Patwardhan [12] showing a positive correlation between different prakriti and HLA alleles, an intense brainstorming among biologists ensued and resulted in coinage of a term Ayurvedic biology [36] as a bid to differentiate Ayurvedic understanding of health and disease from that of conventional biology. Clearly underpinning the importance of prakriti to Ayurvedic understanding, Valiathan, the proponent of Ayurvedic biology, stated, “Since innate disposition determines the manifestation of disease and individual response to treatment, one of the first things a physician does is to determine the prakriti of his patient. This is necessary to personalize the treatment in accordance to the basic principles of Ayurveda. It is clearly suggested that dosa prakriti represents phenotypes” [36]. These initial visions and subsequent efforts by Indian academy of science (IAS) and Indian National Science Academy (INSA) provoked the Government of India to launch an innovative project intended to make genomic variation analysis and gene expression profiling of human dosha prakriti based on the principles of Ayurveda. Con sequential to the approaches made to define Ayurvedic genomics [11, 12], a further advancement is made by the identification of biochemical correlates and whole genome expression to the extreme constitutional types as described in Ayurveda [15]. This landmark study interestingly was able to reveal differences at gene expression level, biochemical level, and also genomic level in different phenotypic groups as per the Ayurvedic classification. Differential gene expression is possibly the concept, which looks more appealing with reference to prakriti as it permits various internal and external factors to operate at different levels to make a final cumulative conglomeration of features in the form of phenotype. Some approaches have recently been made to identify the role of various signals in differential gene expression during the developmental phases. It was noted in these studies that specific signals were able to produce specific gene expressions determining the physiological fate of the cell line [24]. This is again in accordance with the fundamentals of prakriti, which repeatedly says that various factors operating at the time of conception and also during the developmental phase of the fetus finally determine the prakriti of an individual.

It would be of interest to note that the concept of prakriti is luring scientists for its novelty since long. Almost a decade back, it was seriously thought as an important factor determining the final outcome of any therapeutic intervention in a given population. Dah anukar and Thatte [1] in a revealing study were able to correlate the therapeutic outcomes with phenotypical specifications as described in Ayurveda [1]. Incidentally, it can also be noted that similar phenotype-response correlation studies are usually done in almost every postgraduate research work conducted so far at various Ayurvedic institutes in India [19].