

# Two sample MR report

---

## Beta-hydroxyisovalerate levels against Malignant_melanoma_of_skin

Date: **03 January, 2026**

---

### Results from two sample MR:


|method                    | nsnp|          b|        se|      pval|
|:-------------------------|----:|----------:|---------:|---------:|
|MR Egger                  |    5| -0.3621300| 0.1811637| 0.1394732|
|Weighted median           |    5| -0.1976936| 0.0862826| 0.0219499|
|Inverse variance weighted |    5| -0.1517443| 0.0685220| 0.0267921|
|Simple mode               |    5| -0.2100509| 0.1024645| 0.1096920|
|Weighted mode             |    5| -0.2084356| 0.0963964| 0.0966424|

---

### Heterogeneity tests


|method                    |        Q| Q_df|    Q_pval|
|:-------------------------|--------:|----:|---------:|
|MR Egger                  | 2.685857|    3| 0.4426361|
|Inverse variance weighted | 4.244624|    4| 0.3739108|

--- 

### Test for directional horizontal pleiotropy


| egger_intercept|        se|      pval|
|---------------:|---------:|---------:|
|       0.0393574| 0.0315236| 0.3004048|

--- 

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


| snp_r2.exposure| snp_r2.outcome|correct_causal_direction | steiger_pval|
|---------------:|--------------:|:------------------------|------------:|
|       0.0002681|              0|TRUE                     |    0.1553167|

Note - R^2 values are approximate

---

### Forest plot of single SNP MR

![plot of chunk chunk5](figure/Betahydroxyisovalerate_levels_against_Malignantmelanomaofskinchunk5-1.png)

---

### Comparison of results using different MR methods

![plot of chunk chunk6](figure/Betahydroxyisovalerate_levels_against_Malignantmelanomaofskinchunk6-1.png)

---

### Funnel plot

![plot of chunk chunk7](figure/Betahydroxyisovalerate_levels_against_Malignantmelanomaofskinchunk7-1.png)

---

### Leave-one-out sensitivity analysis

![plot of chunk chunk8](figure/Betahydroxyisovalerate_levels_against_Malignantmelanomaofskinchunk8-1.png)
