## 3 Results
### Expression of Up- and Down-Regulated Genes  
Meta-analyses of selected microarray datasets using ExAtlas software estimated 207 significant genes using a random-effect model, of which 109 genes were down-regulated and 98 genes were up-regulated in the patients (both endometriosis and RPL patients taken together) compared to healthy controls. Figure 3 shows clustered heatmaps of the five datasets comprising the expression of the up-regulated and down-regulated DEGs. Based on the expression values of the DEGs, the datasets are clearly clustered into two groups, namely endometriosis and RPL. It is evident from Figure 3 that both the groups--endometriosis and RPL--have a similar pattern of expression of genes. In Figure 3, effect value refers to the log ratio of gene expression change/difference compared to control or study-wide mean or median. Figure 2: Value distribution (box plots) performed in GEO2R of the 5 datasets of endometriosis (GSE7305 (**A**), GSE58178 (**C**), GSE23339 (**D**)) and recurrent pregnancy loss (GSE26787 (**B**) and GSE111974 (**E**)) displaying the distribution of expression values of each sample within a dataset. The plot is useful for determining whether the dataset is normalized, i.e., the value distributions are median-centered across samples. NA analysis revealed 685 DEGs, of which 236 were up-regulated and 449 were down-regulated. When the results of both EA and NA were compared, 120 genes were found to be common. The top 25 DEGs from the above-mentioned 120 genes are listed in Table 2 based on their fold change (FC) values along with their Entrez ID, log-ratio combined and FDR value. Interestingly, among all the DEGs, the _TWIST2_ gene was found to possess the highest fold change value (3.494), which can be considered as a significant observation since the same gene has been found to have the highest fold change value in the case of NA analyses. Among these top 25 DEGs, 60% were down-regulated as evident from their log-ratio combined value while the rest 40% were up-regulated (Table 2). Thus, the down-regulated genes overweighed the scale as compared to the up-regulated genes. \begin{table}
\begin{tabular}{c c c c c} \hline
**Gene Symbol** & **Entrez ID** & **Log Ratio Combined** & **Fold Change** & **FDR \({}^{*}\)** \\ \hline
1.1. TWIST2 & Twist Family Bhlh Transcription Factor 2 & \(-\)0.5434 & 3.494 & 8.79 \(\times\) 10\({}^{-11}\) \\ _CA12_ & Carbonic Anhydrase XII & \(-\)0.5111 & 3.244 & 0.001487 \\ _PGBD5_ & PiggyBac Transposable Element Derived 5 & \(-\)0.4782 & 3.007 & 0.002422 \\ _H19_ & H19, Imprinted Maternally Expressed & \(-\)0.4696 & 2.948 & 0.000894 \\ _TGCD_ & Sarocyclyan Delta & 0.4523 & 2.833 & 0 \\ _AN04_ & Anoctamin 4 & \(-\)0.4227 & 2.647 & 2.42 \(\times\) 10\({}^{-5}\) \\ _CHN2_ & Chimerin 2 & 0.4002 & 2.513 & 8.01 \(\times\) 10\({}^{-7}\) \\ _MLPH_ & Melanophilin & \(-\)0.3955 & 2.486 & 3.27 \(\times\)10\({}^{-6}\) \\ _PLPP1_ & Phospholipid Phosphatase 1 & \(-\)0.3872 & 2.439 & 0.004665 \\ _NR4A2_ & Nuclear Receptor Subfamily 4 Group A & 0.3829 & 2.415 & 0.0217 \\ _DACH1_ & Dachshund Family Transcription Factor 1 & \(-\)0.3827 & 2.414 & 3.07 \(\times\)10\({}^{-8}\) \\ _ADAMTS19_ & Thrombospondin Type 1 Motif 19 & \(-\)0.3787 & 2.392 & 0.004645 \\ _VLDLR_ & Very Low-Density Lipoprotein Receptor & 0.3534 & 2.256 & 0.007674 \\ _NFIB_ & Nuclear Factor I/B & 0.3519 & 2.249 & 4.80 \(\times\) 10\({}^{-6}\) \\ _PCSK6_ & Proprotein Convertase Subtilisin/Kexin & 0.3468 & 2.223 & 0.0154 \\ \multicolumn{5}{c}{Type 6} \\ _GALNT10_ & Polypeptide & 0.334 & 2.158 & 0 \\ _TGM2_ & Transglutaminase 2 & \(-\)0.3236 & 2.107 & 0.006722 \\ _CREG1_ & Cellular Repressor Of E1A-Stimulated & 0.3113 & 2.048 & 0.0175 \\ \multicolumn{5}{c}{Genes 1} \\ \hline \end{tabular}
\end{table} 
Table 2: Top 25 up-regulated and down-regulated genes of the microarray meta-analyses along with their fold change values.