Datos PCR
Manuel Corrales
2026-02-18
Para poner el Chunk es Command + Option + I Se realizará un ejemplo de análisis de datos
# install.packages("pacman")
library(pacman)
# Cargar paquetes necesarios
p_load("ggplot2", #Grafica
"dplyr", #facilita manejo de datos
"vroom")Llamar a base de datos
Datos_PCR <- vroom(file="https://raw.githubusercontent.com/ManuelLaraMVZ/Metabolomica_2026_1/refs/heads/main/Datos_ejercicio_PCR1.1.csv")## Rows: 1001 Columns: 7
## ── Column specification ────────────────────────────────────────────────────────
## Delimiter: ","
## chr (1): Gen
## dbl (6): C1, C2, C3, T1, T2, T3
##
## ℹ Use `spec()` to retrieve the full column specification for this data.
## ℹ Specify the column types or set `show_col_types = FALSE` to quiet this message.# Visualizar datos
Datos_PCR## # A tibble: 1,001 × 7
## Gen C1 C2 C3 T1 T2 T3
## <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
## 1 B-actina 19.9 20.2 19.9 20.0 20.1 19.9
## 2 Gene_1 23.9 23.0 24.0 21.7 22.4 21.0
## 3 Gene_2 24.5 22.9 25.5 21.3 23.3 24.3
## 4 Gene_3 28.1 25.0 23.9 19.1 23.3 19.7
## 5 Gene_4 25.1 24.7 27.4 20.6 19.4 25.0
## 6 Gene_5 25.3 19.9 25.3 27.2 17.9 23.8
## 7 Gene_6 28.4 27.1 23.8 21.9 26.4 22.7
## 8 Gene_7 25.9 25.5 21.4 23.8 22.5 23.1
## 9 Gene_8 22.5 29.8 23.7 21.6 22.8 22.4
## 10 Gene_9 23.6 26.4 29.1 23.2 19.6 21.1
## # ℹ 991 more rowsAislar genes de referencia para cada condición
Gen_ref <- Datos_PCR %>%
filter(Gen == "B-actina") %>%
slice(1) # Asegura que solo se tome una fila
Gen_ref## # A tibble: 1 × 7
## Gen C1 C2 C3 T1 T2 T3
## <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
## 1 B-actina 19.9 20.2 19.9 20.0 20.1 19.9Generar base de datos con genes de interés
Gen_int <- Datos_PCR %>%
filter(Gen != "B-actina")
Gen_int## # A tibble: 1,000 × 7
## Gen C1 C2 C3 T1 T2 T3
## <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
## 1 Gene_1 23.9 23.0 24.0 21.7 22.4 21.0
## 2 Gene_2 24.5 22.9 25.5 21.3 23.3 24.3
## 3 Gene_3 28.1 25.0 23.9 19.1 23.3 19.7
## 4 Gene_4 25.1 24.7 27.4 20.6 19.4 25.0
## 5 Gene_5 25.3 19.9 25.3 27.2 17.9 23.8
## 6 Gene_6 28.4 27.1 23.8 21.9 26.4 22.7
## 7 Gene_7 25.9 25.5 21.4 23.8 22.5 23.1
## 8 Gene_8 22.5 29.8 23.7 21.6 22.8 22.4
## 9 Gene_9 23.6 26.4 29.1 23.2 19.6 21.1
## 10 Gene_10 24.1 24.1 23.9 21.9 24.3 21.3
## # ℹ 990 more rowsAnalisis
DCT <- Gen_int %>%
mutate(
DC1 = C1 - pull(Gen_ref, C1),
DC2 = C2 - pull(Gen_ref, C2),
DC3 = C3 - pull(Gen_ref, C3),
DT1 = T1 - pull(Gen_ref, T1),
DT2 = T2 - pull(Gen_ref, T2),
DT3 = T3 - pull(Gen_ref, T3)
) %>%
mutate(
DosDCTC1 = 2^-DC1,
DosDCTC2 = 2^-DC2,
DosDCTC3 = 2^-DC3,
DosDCTT1 = 2^-DT1,
DosDCTT2 = 2^-DT2,
DosDCTT3 = 2^-DT3
) %>%
mutate(
DosDCTCx = (DosDCTC1 + DosDCTC2 + DosDCTC3) / 3,
DosDCTTx = (DosDCTT1 + DosDCTT2 + DosDCTT3) / 3
) %>%
mutate(
DosDDCT = DosDCTTx / DosDCTCx # Corrección aquÃ
)
# Mostrar resultados
DCT## # A tibble: 1,000 × 22
## Gen C1 C2 C3 T1 T2 T3 DC1 DC2 DC3 DT1 DT2
## <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
## 1 Gene_1 23.9 23.0 24.0 21.7 22.4 21.0 4.02 2.81 4.12 1.72 2.27
## 2 Gene_2 24.5 22.9 25.5 21.3 23.3 24.3 4.68 2.72 5.61 1.37 3.18
## 3 Gene_3 28.1 25.0 23.9 19.1 23.3 19.7 8.26 4.76 4.06 -0.876 3.22
## 4 Gene_4 25.1 24.7 27.4 20.6 19.4 25.0 5.28 4.54 7.58 0.626 -0.689
## 5 Gene_5 25.3 19.9 25.3 27.2 17.9 23.8 5.40 -0.298 5.49 7.22 -2.17
## 6 Gene_6 28.4 27.1 23.8 21.9 26.4 22.7 8.57 6.88 3.91 1.95 6.29
## 7 Gene_7 25.9 25.5 21.4 23.8 22.5 23.1 6.06 5.30 1.52 3.85 2.34
## 8 Gene_8 22.5 29.8 23.7 21.6 22.8 22.4 2.61 9.63 3.85 1.65 2.63
## 9 Gene_9 23.6 26.4 29.1 23.2 19.6 21.1 3.77 6.17 9.23 3.24 -0.507
## 10 Gene_10 24.1 24.1 23.9 21.9 24.3 21.3 4.25 3.91 4.02 1.92 4.14
## # ℹ 990 more rows
## # ℹ 10 more variables: DT3 <dbl>, DosDCTC1 <dbl>, DosDCTC2 <dbl>,
## # DosDCTC3 <dbl>, DosDCTT1 <dbl>, DosDCTT2 <dbl>, DosDCTT3 <dbl>,
## # DosDCTCx <dbl>, DosDCTTx <dbl>, DosDDCT <dbl>Aislar datos
Datos_grafica <- DCT %>%
select("Gen", "DosDDCT")
Datos_grafica## # A tibble: 1,000 × 2
## Gen DosDDCT
## <chr> <dbl>
## 1 Gene_1 3.69
## 2 Gene_2 2.59
## 3 Gene_3 30.6
## 4 Gene_4 30.9
## 5 Gene_5 3.59
## 6 Gene_6 5.36
## 7 Gene_7 0.955
## 8 Gene_8 2.79
## 9 Gene_9 21.9
## 10 Gene_10 3.82
## # ℹ 990 more rowsGrafica de barras
Grafica_PCR <- ggplot(Datos_grafica,
aes(x = Gen,
y = DosDDCT)) + # fill por Gen para colores distintos
geom_col() +
labs(title = "Expresión relativa de genes",
subtitle = "Normalización con B-actina como referencia",
caption = "Diseño: XXXX") +
theme_minimal(base_size = 14) + # estilo minimalista
theme(plot.background = element_rect(fill = "white", color = NA),
panel.background = element_rect(fill = "white", color = NA)) +
scale_fill_brewer(palette = "Set3") # paleta con colores distintos
Grafica_PCR
Gráfica de regresión lineal
Datos_regresion <- DCT %>%
select ("Gen","DosDCTCx","DosDCTTx")
Datos_regresion## # A tibble: 1,000 × 3
## Gen DosDCTCx DosDCTTx
## <chr> <dbl> <dbl>
## 1 Gene_1 0.0874 0.322
## 2 Gene_2 0.0704 0.182
## 3 Gene_3 0.0334 1.02
## 4 Gene_4 0.0247 0.763
## 5 Gene_5 0.425 1.53
## 6 Gene_6 0.0259 0.139
## 7 Gene_7 0.129 0.123
## 8 Gene_8 0.0781 0.218
## 9 Gene_9 0.0297 0.651
## 10 Gene_10 0.0603 0.231
## # ℹ 990 more rowsGraficar regresión
Grafica_regresion <- ggplot(Datos_regresion,
aes(x = DosDCTCx,
y = DosDCTTx)) +
geom_point(size = 3, color = "steelblue") + # puntos más grandes y con color
geom_abline(intercept = 0, slope = 1, # lÃnea con pendiente 1
color = "red", linetype = "dashed", size = 1) +
theme_minimal(base_size = 14) + # estilo limpio
labs(title = "Regresión ΔΔCt",
subtitle = "Comparación entre control y tratamiento",
x = "Control (2^-ΔCt)",
y = "Tratamiento (2^-ΔCt)") +
theme(plot.title = element_text(face = "bold", hjust = 0.5),
plot.subtitle = element_text(hjust = 0.5))## Warning: Using `size` aesthetic for lines was deprecated in ggplot2 3.4.0.
## ℹ Please use `linewidth` instead.
## This warning is displayed once every 8 hours.
## Call `lifecycle::last_lifecycle_warnings()` to see where this warning was
## generated.Grafica_regresion