diff --git a/src/mixtures/mixturemodel.jl b/src/mixtures/mixturemodel.jl
index 91f3d6150..d2eaba9f0 100644
--- a/src/mixtures/mixturemodel.jl
+++ b/src/mixtures/mixturemodel.jl
@@ -135,13 +135,13 @@ function MixtureModel(components::Vector{C}, prior::Categorical) where C<:Distri
     MixtureModel{VF,VS,C}(components, prior)
 end
 
-MixtureModel(components::Vector{C}, p::Vector{Float64}) where {C<:Distribution} =
+MixtureModel(components::Vector{C}, p::VT) where {C<:Distribution,VT<:AbstractVector{<:Real}} =
     MixtureModel(components, Categorical(p))
 
 _construct_component(::Type{C}, arg) where {C<:Distribution} = C(arg)
 _construct_component(::Type{C}, args::Tuple) where {C<:Distribution} = C(args...)
 
-function MixtureModel(::Type{C}, params::AbstractArray, p::Vector{Float64}) where C<:Distribution
+function MixtureModel(::Type{C}, params::AbstractArray, p::Vector{T}) where {C<:Distribution,T<:Real}
     components = C[_construct_component(C, a) for a in params]
     MixtureModel(components, p)
 end
@@ -304,7 +304,7 @@ function _cdf(d::UnivariateMixture, x::Real)
     return r
 end
 
-cdf(d::UnivariateMixture{Continuous}, x::Float64) = _cdf(d, x)
+cdf(d::UnivariateMixture{Continuous}, x::Real) = _cdf(d, x)
 cdf(d::UnivariateMixture{Discrete}, x::Int) = _cdf(d, x)
 
 
@@ -359,7 +359,7 @@ function _mixlogpdf1(d::AbstractMixtureModel, x)
     p = probs(d)
     @assert length(p) == K
 
-    lp = Vector{Float64}(undef, K)
+    lp = Vector{eltype(x)}(undef, K)
     m = -Inf   # m <- the maximum of log(p(cs[i], x)) + log(pri[i])
     for i = 1:K
         @inbounds pi = p[i]
@@ -386,7 +386,7 @@ function _mixlogpdf!(r::AbstractArray, d::AbstractMixtureModel, x)
     p = probs(d)
     @assert length(p) == K
     n = length(r)
-    Lp = Matrix{Float64}(undef, n, K)
+    Lp = Matrix{eltype(x)}(undef, n, K)
     m = fill(-Inf, n)
     for i = 1:K
         @inbounds pi = p[i]
@@ -501,15 +501,15 @@ componentwise_logpdf!(r::AbstractVector, d::MultivariateMixture, x::AbstractVect
 componentwise_logpdf!(r::AbstractMatrix, d::UnivariateMixture, x::AbstractVector) = _cwise_logpdf!(r, d, x)
 componentwise_logpdf!(r::AbstractMatrix, d::MultivariateMixture, x::AbstractMatrix) = _cwise_logpdf!(r, d, x)
 
-componentwise_pdf(d::UnivariateMixture, x::Real) = componentwise_pdf!(Vector{Float64}(undef, ncomponents(d)), d, x)
-componentwise_pdf(d::UnivariateMixture, x::AbstractVector) = componentwise_pdf!(Matrix{Float64}(undef, length(x), ncomponents(d)), d, x)
-componentwise_pdf(d::MultivariateMixture, x::AbstractVector) = componentwise_pdf!(Vector{Float64}(undef, ncomponents(d)), d, x)
-componentwise_pdf(d::MultivariateMixture, x::AbstractMatrix) = componentwise_pdf!(Matrix{Float64}(undef, size(x,2), ncomponents(d)), d, x)
+componentwise_pdf(d::UnivariateMixture, x::Real) = componentwise_pdf!(Vector{eltype(x)}(undef, ncomponents(d)), d, x)
+componentwise_pdf(d::UnivariateMixture, x::AbstractVector) = componentwise_pdf!(Matrix{eltype(x)}(undef, length(x), ncomponents(d)), d, x)
+componentwise_pdf(d::MultivariateMixture, x::AbstractVector) = componentwise_pdf!(Vector{eltype(x)}(undef, ncomponents(d)), d, x)
+componentwise_pdf(d::MultivariateMixture, x::AbstractMatrix) = componentwise_pdf!(Matrix{eltype(x)}(undef, size(x,2), ncomponents(d)), d, x)
 
-componentwise_logpdf(d::UnivariateMixture, x::Real) = componentwise_logpdf!(Vector{Float64}(undef, ncomponents(d)), d, x)
-componentwise_logpdf(d::UnivariateMixture, x::AbstractVector) = componentwise_logpdf!(Matrix{Float64}(undef, length(x), ncomponents(d)), d, x)
-componentwise_logpdf(d::MultivariateMixture, x::AbstractVector) = componentwise_logpdf!(Vector{Float64}(undef, ncomponents(d)), d, x)
-componentwise_logpdf(d::MultivariateMixture, x::AbstractMatrix) = componentwise_logpdf!(Matrix{Float64}(undef, size(x,2), ncomponents(d)), d, x)
+componentwise_logpdf(d::UnivariateMixture, x::Real) = componentwise_logpdf!(Vector{eltype(x)}(undef, ncomponents(d)), d, x)
+componentwise_logpdf(d::UnivariateMixture, x::AbstractVector) = componentwise_logpdf!(Matrix{eltype(x)}(undef, length(x), ncomponents(d)), d, x)
+componentwise_logpdf(d::MultivariateMixture, x::AbstractVector) = componentwise_logpdf!(Vector{eltype(x)}(undef, ncomponents(d)), d, x)
+componentwise_logpdf(d::MultivariateMixture, x::AbstractMatrix) = componentwise_logpdf!(Matrix{eltype(x)}(undef, size(x,2), ncomponents(d)), d, x)
 
 
 ## Sampling
diff --git a/src/mixtures/unigmm.jl b/src/mixtures/unigmm.jl
index 04930ea34..f86903194 100644
--- a/src/mixtures/unigmm.jl
+++ b/src/mixtures/unigmm.jl
@@ -1,17 +1,17 @@
 # Univariate Gaussian Mixture Models
 
-struct UnivariateGMM <: UnivariateMixture{Continuous,Normal}
+struct UnivariateGMM{VT1<:AbstractVector{<:Real},VT2<:AbstractVector{<:Real}} <: UnivariateMixture{Continuous,Normal}
     K::Int
-    means::Vector{Float64}
-    stds::Vector{Float64}
+    means::VT1
+    stds::VT2
     prior::Categorical
 
-    function UnivariateGMM(ms::Vector{Float64}, ss::Vector{Float64}, pri::Categorical)
+    function UnivariateGMM(ms::VT1, ss::VT2, pri::Categorical) where {VT1<:AbstractVector{<:Real},VT2<:AbstractVector{<:Real}}
         K = length(ms)
         length(ss) == K || throw(DimensionMismatch())
         ncategories(pri) == K ||
             error("The number of categories in pri should be equal to the number of components.")
-        new(K, ms, ss, pri)
+        new{VT1,VT2}(K, ms, ss, pri)
     end
 end
 
@@ -25,14 +25,16 @@ probs(d::UnivariateGMM) = probs(d.prior)
 
 mean(d::UnivariateGMM) = dot(d.means, probs(d))
 
+rand(d::UnivariateGMM) = (k = rand(d.prior); d.means[k] + randn() * d.stds[k])
+
 rand(rng::AbstractRNG, d::UnivariateGMM) =
     (k = rand(rng, d.prior); d.means[k] + randn(rng) * d.stds[k])
 
 params(d::UnivariateGMM) = (d.means, d.stds, d.prior)
 
-struct UnivariateGMMSampler <: Sampleable{Univariate,Continuous}
-    means::Vector{Float64}
-    stds::Vector{Float64}
+struct UnivariateGMMSampler{VT1<:AbstractVector{<:Real},VT2<:AbstractVector{<:Real}} <: Sampleable{Univariate,Continuous}
+    means::VT1
+    stds::VT2
     psampler::AliasTable
 end
 
diff --git a/test/mixture.jl b/test/mixture.jl
index 99d90fd15..dbc8c46a9 100644
--- a/test/mixture.jl
+++ b/test/mixture.jl
@@ -1,18 +1,20 @@
 using Distributions, Random
 using Test
+using ForwardDiff: Dual
 
 
 # Core testing procedure
 
 function test_mixture(g::UnivariateMixture, n::Int, ns::Int,
                       rng::Union{AbstractRNG, Missing} = missing)
-    X = zeros(n)
+    if g isa UnivariateGMM
+        T = eltype(g.means)
+    else
+        T = eltype(g)
+    end
+    X = zeros(T, n)
     for i = 1:n
-        if ismissing(rng)
-            X[i] = rand(g)
-        else
-            X[i] = rand(rng, g)
-        end
+        X[i] = rand(g)
     end
 
     K = ncomponents(g)
@@ -27,7 +29,7 @@ function test_mixture(g::UnivariateMixture, n::Int, ns::Int,
     @test mean(g) ≈ mu
 
     # evaluation of cdf
-    cf = zeros(n)
+    cf = zeros(T, n)
     for k = 1:K
         c_k = component(g, k)
         for i = 1:n
@@ -41,8 +43,8 @@ function test_mixture(g::UnivariateMixture, n::Int, ns::Int,
     @test cdf.(g, X) ≈ cf
 
     # evaluation
-    P0 = zeros(n, K)
-    LP0 = zeros(n, K)
+    P0 = zeros(T, n, K)
+    LP0 = zeros(T, n, K)
     for k = 1:K
         c_k = component(g, k)
         for i = 1:n
@@ -68,14 +70,16 @@ function test_mixture(g::UnivariateMixture, n::Int, ns::Int,
     @test componentwise_logpdf(g, X) ≈ LP0
 
     # sampling
-    if ismissing(rng)
-        Xs = rand(g, ns)
-    else
-        Xs = rand(rng, g, ns)
+    if (T isa AbstractFloat)
+        if ismissing(rng)
+            Xs = rand(g, ns)
+        else
+            Xs = rand(rng, g, ns)
+        end
+        @test isa(Xs, Vector{T})
+        @test length(Xs) == ns
+        @test isapprox(mean(Xs), mean(g), atol=0.01)
     end
-    @test isa(Xs, Vector{Float64})
-    @test length(Xs) == ns
-    @test isapprox(mean(Xs), mean(g), atol=0.01)
 end
 
 function test_mixture(g::MultivariateMixture, n::Int, ns::Int,
@@ -164,56 +168,59 @@ end
     Dict("rand(...)" => missing,
          "rand(rng, ...)" => MersenneTwister(123))
 
-@testset "Testing UnivariateMixture" begin
-g_u = MixtureModel(Normal, [(0.0, 1.0), (2.0, 1.0), (-4.0, 1.5)], [0.2, 0.5, 0.3])
-@test isa(g_u, MixtureModel{Univariate, Continuous, Normal})
-@test ncomponents(g_u) == 3
-test_mixture(g_u, 1000, 10^6, rng)
-test_params(g_u)
-@test minimum(g_u) == -Inf
-@test maximum(g_u) == Inf
-@test extrema(g_u) == (-Inf, Inf)
-
-g_u = MixtureModel([TriangularDist(-1,2,0),TriangularDist(-.5,3,1),TriangularDist(-2,0,-1)])
-@test minimum(g_u) ≈ -2.0
-@test maximum(g_u) ≈ 3.0
-@test extrema(g_u) == (minimum(g_u), maximum(g_u))
-@test insupport(g_u, 2.5) == true
-@test insupport(g_u, 3.5) == false
-
-g_u = UnivariateGMM([0.0, 2.0, -4.0], [1.0, 1.2, 1.5], Categorical([0.2, 0.5, 0.3]))
-@test isa(g_u, UnivariateGMM)
-@test ncomponents(g_u) == 3
-test_mixture(g_u, 1000, 10^6, rng)
-test_params(g_u)
-@test minimum(g_u) == -Inf
-@test maximum(g_u) == Inf
-@test extrema(g_u) == (-Inf, Inf)
-end
+    @testset "Testing UnivariateMixture" begin
+        g_u = MixtureModel(Normal, [(0.0, 1.0), (2.0, 1.0), (-4.0, 1.5)], [0.2, 0.5, 0.3])
+        @test isa(g_u, MixtureModel{Univariate, Continuous, Normal})
+        @test ncomponents(g_u) == 3
+        test_mixture(g_u, 1000, 10^6, rng)
+        test_params(g_u)
+        @test minimum(g_u) == -Inf
+        @test maximum(g_u) == Inf
+        @test extrema(g_u) == (-Inf, Inf)
+
+        g_u = MixtureModel([TriangularDist(-1,2,0),TriangularDist(-.5,3,1),TriangularDist(-2,0,-1)])
+        @test minimum(g_u) ≈ -2.0
+        @test maximum(g_u) ≈ 3.0
+        @test extrema(g_u) == (minimum(g_u), maximum(g_u))
+        @test insupport(g_u, 2.5) == true
+        @test insupport(g_u, 3.5) == false
+
+        μ = [0.0, 2.0, -4.0]; σ = [1.0, 1.2, 1.5]; p = [0.2, 0.5, 0.3]
+        for T = [Float64, Dual]
+            g_u = UnivariateGMM(map(Dual, μ), map(Dual, σ), Categorical(p))
+            @test isa(g_u, UnivariateGMM)
+            @test ncomponents(g_u) == 3
+            test_mixture(g_u, 1000, 10^6, rng)
+            test_params(g_u)
+            @test minimum(g_u) == -Inf
+            @test maximum(g_u) == Inf
+            @test extrema(g_u) == (-Inf, Inf)
+        end
+    end
 
-@testset "Testing MultivariatevariateMixture" begin
-g_m = MixtureModel(
-    IsoNormal[ MvNormal([0.0, 0.0], 1.0),
-               MvNormal([0.2, 1.0], 1.0),
-               MvNormal([-0.5, -3.0], 1.6) ],
-    [0.2, 0.5, 0.3])
-@test isa(g_m, MixtureModel{Multivariate, Continuous, IsoNormal})
-@test length(components(g_m)) == 3
-@test length(g_m) == 2
-@test insupport(g_m, [0.0, 0.0]) == true
-test_mixture(g_m, 1000, 10^6, rng)
-test_params(g_m)
-
-u1 =  Uniform()
-u2 =  Uniform(1.0, 2.0)
-utot =Uniform(0.0, 2.0)
- 
-# mixture supposed to be a uniform on [0.0,2.0]
-unif_mixt =  MixtureModel([u1,u2])
-@test var(utot) ≈  var(unif_mixt)
-@test mean(utot) ≈ mean(unif_mixt)
-for x in -1.0:0.5:2.5
-    @test cdf(utot,x) ≈ cdf(utot,x)
-end
-end
+    @testset "Testing MultivariatevariateMixture" begin
+        g_m = MixtureModel(
+            IsoNormal[ MvNormal([0.0, 0.0], 1.0),
+                       MvNormal([0.2, 1.0], 1.0),
+                       MvNormal([-0.5, -3.0], 1.6) ],
+            [0.2, 0.5, 0.3])
+        @test isa(g_m, MixtureModel{Multivariate, Continuous, IsoNormal})
+        @test length(components(g_m)) == 3
+        @test length(g_m) == 2
+        @test insupport(g_m, [0.0, 0.0]) == true
+        test_mixture(g_m, 1000, 10^6, rng)
+        test_params(g_m)
+
+        u1 =  Uniform()
+        u2 =  Uniform(1.0, 2.0)
+        utot =Uniform(0.0, 2.0)
+
+        # mixture supposed to be a uniform on [0.0,2.0]
+        unif_mixt =  MixtureModel([u1,u2])
+        @test var(utot) ≈  var(unif_mixt)
+        @test mean(utot) ≈ mean(unif_mixt)
+        for x in -1.0:0.5:2.5
+            @test cdf(utot,x) ≈ cdf(utot,x)
+        end
+    end
 end