covariant type T occurs in invariant position

I'm moving my first steps in Scala and I would like to make the following code works:

trait Gene[+T] {
    val gene: Array[T]
}

The error that the compiler gives is: covariant type T occurs in invariant position in type => Array[T] of value gene

I know I could do something like:

trait Gene[+T] {
    def gene[U >: T]: Array[U]
}

but this doesn't solve the problem because I need a value: pratically what I'm trying to say is "I don't care of the inside type, I know that genes will have a gene field that return its content". (the +T here is because I wanna do something like type Genome = Array[Gene[Any]] and then use it as a wrapper against the single gene classes so I can have a heterogeneous array type) Is it possible to do it in Scala or I'm simply taking a wrong approach? Would it be better to use a different structure, like a Scala native covariant class?

Thanks in advance!

P.S.: I've also tried with class and abstract class instead than trait but always same results!

EDIT: with kind suggestion by Didier Dupont I came to this code:

package object ga {


  class Gene[+T](val gene: Vector[T]){

    def apply(idx: Int) = gene(idx)

    override def toString() = gene.toString

  }

  implicit def toGene[T](a: Vector[T]) = new Gene(a)

  type Genome = Array[Gene[Any]]

}

package test

import ga._

object Test {
    def main(args: Array[String]) {
        val g = Vector(1, 3, 4)

        val g2 = Vector("a", "b")

        val genome1: Genome = Array(g, g2)

        println("Genome")

        for(gene <- genome1) println(gene.gene) 
    }
}

So I now think I can put and retrieve data in different types and use them with all type checking goodies!