Genetic loading

Haploids are sporophytes with the gametophytic chromosome number. Haploids (2x) of tetraploid potato cultivars provide a mechanism for direct gene transfer from wild 2x relatives and allow breeders to work at the diploid level. As discussed below, selection progress is more rapid with diploids than tetraploids. Haploids can also be used to measure the genetic load in the tetraploids from which they are derived, since deleterious alleles hidden in tetraploids are often expressed in haploids. 

Factors that may influence whether trauma exposure progresses to PTSD include one s natural resiliency, genetic loading, the type of trauma, whether the trauma is natural or man-made, past traumas, and psychiatric comorbidities (Matthews Mossefin, 2006). 

Genetic studies (primarily derived from population, family, twin, and adoptive studies) suggest that certain depressive disorders may have a genetic loading, especially bipolar and imipolar depression. 

Points 1 and 2 indicate that the idea relationship nowadays has a distinct genetical load, also when it has not (yet) been possible (or will never be possible) to find out the actual genetical situation. 

Genetic load was not understood. Recombinant organisms are normally at a severe disadvantage in a natural environment. Under strong selection, recombinants can be forced to survive in the laboratory. However, often the rDNA is still rapidly lost, for example, where high transcription rates are involved. 

There are no estimates available of inbreeding depression and genetic load in subalpine larch. 

Sorensen, F.C. 1969. Embryonic genetic load in coastal Douglas-fir, Pseudotsuga menziesii var. menziesii. American Naturalist 103 389-398. 

---