

# Two sample MR report

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## Diacylglycerol (18:1_18:2) levels against Malignant_melanoma_of_skin

Date: **04 January, 2026**

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### Results from two sample MR:


|method                    | nsnp|         b|        se|      pval|
|:-------------------------|----:|---------:|---------:|---------:|
|MR Egger                  |    6| 0.3513038| 0.1529878| 0.0832787|
|Weighted median           |    6| 0.1797703| 0.0752319| 0.0168690|
|Inverse variance weighted |    6| 0.1785973| 0.0598222| 0.0028314|
|Simple mode               |    6| 0.1813585| 0.1080651| 0.1541419|
|Weighted mode             |    6| 0.2249873| 0.0804386| 0.0381281|

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### Heterogeneity tests


|method                    |         Q| Q_df|    Q_pval|
|:-------------------------|---------:|----:|---------:|
|MR Egger                  | 0.5640279|    4| 0.9669759|
|Inverse variance weighted | 2.0684497|    5| 0.8395950|

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### Test for directional horizontal pleiotropy


| egger_intercept|        se|      pval|
|---------------:|---------:|---------:|
|       -0.032461| 0.0264653| 0.2872545|

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### Test that the exposure is upstream of the outcome


| snp_r2.exposure| snp_r2.outcome|correct_causal_direction | steiger_pval|
|---------------:|--------------:|:------------------------|------------:|
|       0.0006629|              0|TRUE                     |    0.0432205|

Note - R^2 values are approximate

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### Forest plot of single SNP MR

![plot of chunk chunk5](figure/Diacylglycerol_181182_levels_against_Malignantmelanomaofskinchunk5-1.png)

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### Comparison of results using different MR methods

![plot of chunk chunk6](figure/Diacylglycerol_181182_levels_against_Malignantmelanomaofskinchunk6-1.png)

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### Funnel plot

![plot of chunk chunk7](figure/Diacylglycerol_181182_levels_against_Malignantmelanomaofskinchunk7-1.png)

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### Leave-one-out sensitivity analysis

![plot of chunk chunk8](figure/Diacylglycerol_181182_levels_against_Malignantmelanomaofskinchunk8-1.png)
