Obesity is a chronic and growing problem which affects millions of people all over the world. It's a complex disorder resulting from interaction environmental and genetics factors [1]. Obesity is highly prevalent condition; it affects 25-30% of children and adolescents [2]. Over weight in adolescence is considered an important predictor of long term morbidity. Obesity is considered to be a multifactorial disease involving genetics, physiology and environmental and is influenced by culture message. Family members share diet, culture back ground and many aspects of life style as well as genes [2,3]. Family studies indicate that as much as 20-60% of variation in body fat may be due to genetic causes’. The degree of overweight and obesity is assessed with body mass index (weight divided by height square). A body mass index from 26-30 in adult males (in kg/m2) and from 25-30 in adult females is considered overweight> an index of 30 or greater is obese. Adolescence is derived from the Latin word "Adolescence" which means "to grow up". It occupies roughly the second decade of life. It's a crucial and dynamic phase during which is transition from childhood to adulthood [4,5]. Obesity is resulting from the interaction between variety of environmental and genetics factors such as leptin gene which is adipocyte-secreted hormone that regulates food intake and body weight. Leptin circulates in the blood in both free and protein-bound form where the free form of leptin is the biologically active form. The equilibrium between free and bound leptin regulates leptin bioavailability [6-8]. Leptin is primarily synthesized and secreted by white adipose tissue and act through a complex mechanism involving receptors in the brain and several peripheral tissues. It's plasma concentration varies in proportion to fat mass [9].

Sample Collection

Data and information on obese students were obtained from Thi-Qar province secondary school for year 2022. The number of students is 500 students was collected information on samples collection, gender, family history, obese period and occupation.

Designing of Primers

Primer for amplification of partial gene sequences of leptin gene was designed as according to kit method (DNA extraction kit cat. NO. GS100) and analyzed for their factures using [7].

Confirmation of Leptin Gene in Adolescent

DNA samples blood from students were extracted based on the leaflet attached to kit extraction in manufactured by Gene aid (Korean origin). PCR technique was used to amplify leptin gene according to the method of Eshkoor et al. [7]. DNA samples were detected by electrophoresis [7]. The PCR reaction and cycling condition are described in Table 1 and 2. The PCR product was checked on 1.2% gel and sequences were confirmed (Table 3).

Table1: The Primers Sequences of Leptin Gene Using in PCR

Table 2: PCR reaction mixture to confirm leptin gene 

Table 3: The PCR Program for the Amplification of Leptin Gene

Anthropometric Measurements

 So make many measurements for IBM, weight, height, waist and hip circumference, mid arm and skin thickness.

Statical Analysis: Statical analysis using SPSS software [8].

Obesity Distribution

Prevalence of obesity among secondary school in Thi-qar Table 7 was 500, age between 8-15 year, male number was 288. While female was 312, prevalence of obesity was higher in female (14.3%) than male (11.65) as show in Table 4.

Table 4: Prevalence of Obesity Among Secondary School Students in Thi-Qar 

Obesity prevalence 

The results of the current study showed The highly percentage of gene deletion in obese students 80% compare with non-obese groups 48% with significant different at (p<0.05) Results statically analysis have been shown significant different at (p<0.05). gene deletion increased about (4.33) four times obese compare with non- obese group OR = 4.33,95% (CI = 1.78-10.52), as show in Table 5. There is a significant different at (p<0.05).

Table 5: Comparison Between Obese and Non-Obese Gene Deletion 

 OR =Odd ratio 95% CI= 95% Confidence Interval

Gender 

When compare between male and female obese, the gene absent twice time in female as shown in Table 6.

Table 6: Comparison Between Male Obese and Femal Obese Gene Deletion 

 OR: Odd ratio 95%, CI: 95% Confidence Interval

Obese Period

A correlation between the genotypes of the leptin gene and the periods of obesity for obese students that have obese more than 10 years compare with that have obesity less than 10 years, as the results show significant difference (OR = 10,95% CI = 2.501-0.02) between two different periods as shown in Table 7.

Table 7: Genotypes Distribution of Leptin Gene Samples Adolescent Obesity According To Obese Periods

Anthropometric Measurements

Mean weight of students according to age and sex Show that the mean body weight was increased in older age and male was higher than female. Beside that skin thickness in male was higher than female, while waist in female was less than male, female mean weight was higher than male Table 8.

Table 8: Distribution of sample according to age, mean weight, mean height triceps skin fold thickness, waist circumference and hip circumference., triceps skin fold thickness, waist circumference and hip circumference

Obesity has become a real public health problem as it carries a risk of pathological consequences which may sometimes be life-threatening. Obesity is a significantly associated with diabetes, gall bladder and rheumatologic disease [6,10,11]. It cause a great loss in quality of life and a lot of suffering, not for the obese individual but also their families. In the western world 6-15 of school children and 20-30% of adolescent are overweight or obese [8,12]. In the present study, the prevalence of obesity among adolescence of the studied sample was 25.9% with 11.6% in male and 14.3% in female.

The wide differences in results can be explained by the differences in age of studied sample (children and adolescence) also the use different definition of obesity weather based on BMI for chart or on percentiles. Present study gender was shown to be associated with obesity and leptin gene polymorphisms were significantly associated with gender. It was also revealed the leptin had an effected on obesity via induction of sweet materials. Leptin also activate transduction cascade. In sweet responsive cell, with one involving CAMP. In female sugar increases intracellular camp which activate protein kinase A and closes k channels mediated by phosphorylation. obesity is multifactorial as it is based on genetics, behavior and environmental factors, various genetic disorder can cause obesity in isolation or mostly in syndromic form. Environmental play key role in shaping an individual habits and life style, behavioral problem also relates to increase in meal quantity at home and when dining out. Fast foods have high fat and energy contents. Obesity results from an imbalance between food intake and energy expenditure resulting in excessive accumulation of the fat in adipose tissue, liver, muscles and other organs involved in metabolisms. Before the discovery the association of leptin in obesity, there are three theories existed regulating way in the body can regulating body weight; thermoregulation way where maintenance of a basal body temperature through energy expenditure influences weight, where plasma. Glucose regulates all energy store and lipostatic theory where metabolism product of fat circulates in the blood and interacts with various receptor to maintain fat stores, leptin function as a peripheral signal in a negative feedback loop system to control body weight. Women have higher leptin level than men because of an increase in leptin expression in subcutaneous adipose tissue and stimulate of leptin synthesis by estrogen. leptin level are increase by insulin, glucocorticoid and pro-inflammatory cytokines and decreased by catechol amines.

According to these results, we can conclude that obesity is a prevalent disorder among school students in Thi-Qar province, the overall prevalence was 25.9%, the prevalence was higher among female 14.3% than among males 11.6%. Risk factors such as obese periods and gender have been appeared differentiation relationship with the Leptin gene deletion, where the highest percentage was found in obese period more than 15 years. Leptin was play important play in the control of energy balance and insulin action in humans, as evidence by the fact that Leptin deficiency lead to morbid obesity and insulin resistance.

Acknowledgment

I acknowledge the facilities at secondary schools in Thi-Qar Province.

Conflict of Interest

No financial or any other conflicts of interest in this work.

Funding

Self.

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