ASPECTS OF MORPHOGENETIC TRAITS ASSOCIATED WITH PHYSIOLOGICAL COEFFICIENTS RELATED TO INCIDENCE OF OBESITY, HYPERTENSION, AND DIABETES MELLITUS

The vulnerability to develop certain pathophysiological conditions may be linked to the morphogenetic traits of individuals. Hence, this study ascertained the relationship between some morphogenetic traits and physiological coefficients related to incidence of obesity, hypertension, and diabetes mellitus. Morphogenetic traits (height, weight, ABO blood group, Hitchhiker thumb, tongue rolling, and hand clasping) and physiological coefficients; body mass index, blood pressure (BP), random blood sugar (RBS), and fasting blood sugar (FBS) were measured during a free medical outreach in an institution in Eastern Nigeria. Seventy individuals participated; age (15–35 years), females: 36 (51.4%), males: 34 (48.6%), pre-obese (28.6%), obese 1 and 2 (2.9%, 2.9%), and BP (52.9% normal and 34.3% hypotensive). Twenty-five (35.7%) assayed FBS showed 1.4% diabetes, 17.1% pre-diabetes, and 17.1% normal, while 45 (64.3%) assayed RBS showed 57.1% normal and 7.2% pre-diabetes. There was significantly increased incidence of pre-diabetes and diabetes among tongue rollers when compared to non-tongue rollers (p<0.05). Incidence of obesity and hypertension was not significantly associated with tongue rolling. There was significant association between weight and incidence of obesity (p<0.05); no significant association with weight and incidence of hypertension and diabetes. There was also no association between height, ABO blood group, Hitchhiker thumb, hand clasping and incidence of obesity, hypertension, and diabetes (p<0.05). Conclusively, morphogenetic traits such as tongue rolling and body weight were associated with physiological coefficients related to incidence of diabetes and obesity, respectively, supporting the hypothesis that certain morphogenetic traits can be linked to the proneness of individuals to obesity and diabetes.


INTRODUCTION
Human anatomical/physiological variations (both usual and unusual variations) result from mutations, gene flow, and sexual reproduction [1,2]. DNA mutation mediates genetic variation through alteration of the genes of persons in a population [3]. Gene flow gives rise to genetic variation as new persons with different combinations of gene move into a population, leading to movement of genes from one population to another [4]. Sexual reproduction enhances variable gene combinations in a population, leading to genetic variation [5,6]. Morphogenetic traits (physical observable traits that can be inherited either in a single gene or multifactorial pattern) play a role in genetic variation because morphogenetic traits are inherited from parent to offspring and give rise to various human anatomical/physiological variations. Examples of human morphogenetic traits include; height, weight, hand clasping, eye, and hair color. [7]. Several studies have associated various morphogenetic traits to other morphogenetic traits, different anatomical/physiological variations, and the vulnerability of an individual to certain pathophysiological conditions. ABO blood group was associated with the left hand clasping, body weight was associated with obesity, relationship between ABO blood groups and susceptibility to malaria was also reported, etc. [7][8][9][10].
Physiological coefficients related to obesity include height, body weight, and weight circumference as obesity can be determined from body mass index (BMI) expressed as kg/m 2 [11]. Height and weight are morphogenetic traits that can be transferred from parents to offspring [7]. Hypertension and diabetes mellitus are pathophysiological conditions related to alteration in homeostasis of blood pressure (BP) and blood sugar level resulting to its increase in the body [12,13]. The relationship between morphogenetic traits and incidence of obesity, hypertension, and diabetes mellitus is not fully elucidated. This study tends to evaluate the hypothesis that some morphogenetic traits could be an influencing factor over the proneness of individuals toward incidence of obesity, hypertension, and diabetes mellitus. Hence, this study was designed to ascertain the relationship between some morphogenetic trait (height, weight, ABO blood group, Hitchhiker thumb, tongue rolling, and hand clasping) and physiological coefficients (BMI, BP, random blood sugar [RBS], and fasting blood sugar [FBS]).

Study design and sampling
This is a cross-sectional study; simple random technique [7] was used to select volunteered participants during a free medical outreach conducted by 200 level medical students of Gregory University Uturu (an institution in Eastern Nigeria). Total of 70 volunteered subjects participated in the study.

Data analysis
Data obtained were statistically analyzed using SPSS version 25; frequency and percentage analysis was ascertained. Crosstab was used for association between variables and chi-square (X 2 ) test was used to ascertain statistical significance at p<0.05.
This finding suggests that tongue rolling can be linked to the proneness of individuals to diabetes mellitus; thus, tongue rollers may be more prone to diabetes than non-tongue rollers, while other morphogenetic traits measured in this study could not be linked to the proneness of an individual to diabetes mellitus. Although, several studies have been performed on association between tongue rolling and various anatomical/physiological variations [7,20,21]; this study was the first to demonstrate the association between tongue rolling and incidence of diabetes mellitus.
Despites the existence of several morphogenetic traits, the scope of this study was limited to evaluating the relationship between some     Considering the observed relationship between tongue rolling and diabetes mellitus which suggests that tongue roller may be more prone to diabetes mellitus than non-tongue rollers, it is recommended that; 1. Further studies be carried out in higher population, tribe, and ethnicity 2. More studies of this kind should be performed on diabetes mellitus population in different health facility, countries, and continent 3. Association studies of tongue rolling with other morphogenetic traits, anatomical/physiological coefficients as well as pathophysiological conditions should be performed 4. Good nutritional habits are recommended for avoidance of diabetes mellitus especially for the tongue rollers based on the report from this study.

CONCLUSION
This study demonstrated for the 1 st time that the morphogenetic trait (tongue rolling) could be linked to incidence of diabetes mellitus as tongue rollers may be more prone to diabetes than non-tongue rollers. This study also supported reports on the association between weight and obesity as such was observed in the findings. Hence, this report supported the hypothesis that certain morphogenetic traits can be associated with the proneness of an individual to some pathophysiological conditions such as obesity, hypertension, and diabetes mellitus; although no significant association was observed between morphogenetic traits measured in this study and hypertension.

ACKNOWLEDGMENT
Authors express gratitude to Gregory University Uturu, Abia, Nigeria and all volunteered participants for their cooperation which has aided the progress of this study.

CONFLICTS OF INTEREST
The authors declare that they have no conflicts of interest in relation to this research, whether financial, personal, authorship or otherwise, that could affect the research and its results presented in this paper.