A lot of factors found to be related to diseases in one way or another, in the past years many studies showed that there was a risk factor that affects several diseases which is betaine Homocysteine. This study will consider homocysteine level as a factor and a marker for certain types of diseases. This study 75 different patients with different diseases and 40 healthy individuals (control) the current results revealed statistically significant difference among the all studied groups. The results showed that the homocysteine (Hcy) level varies depending on the type of disease. An interesting significant increase of mean serum homocysteine level was recorded in Liver disease, while the lowest mean Hcy concentration was in Hyperthyroidism individuals compared to healthy adults and children (Control) individuals with P-value >0.005 .Serum homocystiene concentration levels were found to increase significantly in liver 171.50±93.92 pg/ml. compared to healthy control 10.31±2.63 pg/ml. with p< 0.0001. The study recorded the highest concentration of homocystiene among all diseases. The results showed that the total Hcy concentrations were significantly higher in this group irrespective of age or gender than in the control group.There was highly significant differences between the healthy control and thyrodim subjects, P< 0.0001. In the first group (hypothyroidism) homocystiene concentration 45.62±13.85 pg/ml. Second group (hyperthyroidism) homocystiene concentration 29.36±6.71 pg/ml. and for healthy control group 10.31±2.63 pg/ml. The results domenstrated increasing level of homocystiene in hypothyroidism more than hyperthyroidism, in comparatment between these two groups the p-value was P< 0.005, While other data indicated that there was high concentration of homocystiene in cardiovascular disease (CVD) patients group 86.73±22.79 pg/ml. with highly statistical significant difference (p<0.0001) when compared with healthy control group, and the mean results of male and female was 95.15±25.60, 74.10±10.55 pg/ml. with P-value (P>0.163) between them.Serum homocystiene concentration levels in Alzheimer’s disease domenstrated significant difference with p< 0.0001 when compared to healthy control subjects 171.50±93.92, 10.31±2.63 respectively. The study showed positive relationship with age.This study showed a significant higher homocysteine concentration between healthy control 10.31±2.63 pg/ml. and diabetic patients 77.00±55.01 pg/ml. with p-value <0.004. There was a positive relationship with glucose test. The other highest homocystiene concentration levels was recorded in renal failure 152.30±38.84 pg/ml. for this study the concentration was increased significantly with p< 0.0001 as compared to control individuals group 10.31±2.63 pg/ml. While serum urea and creatinine concentrations were significant increases in cases (60.1± 54.2 and 1.6±1.8 mg/dl, respectively) compared to controls (25.0±7.1 and 0.69±0.16 mg/dl, respectively) with (p=0.000 and p=0.005, respectively). This disease had a positive relationship with high concentration of serum urea and creatinine.Finally there was a highly significant difference between concentration of homocysteine in healthy control and autistic children (p<0.001). Homocysteine significantly increased in autism patient's 66.80±25.45 pg/ml. compared with healthy control subjects 3.08±1.07 pg/ml.
