The universal GP Training website for everyone, not just Bradford.   Created in 2002 by Dr Ramesh Mehay

Bradford VTS Online Resources:

Clinical Knowledge


Basic genetic terminology

  • Gene: basic unit of genetic information.
      • It is made up of a DNA.
      • DNA helps makes an RNA product that is either directly functional or makes a protein.
  • Chromosomes – the protein strands around which DNA (and hence genes) is anchored.
      • Each human cell contains 23 pairs of homologous (identical) chromosomes. 
      • So, human somatic cells contain 46 chromosomes, i.e., 46 DNA molecules, of various lengths, which form 23 pairs of homologous chromosomes. 
      • 1 of these 23 pairs is ONE pair of sex chromosome – which consists of either 2 X chromosomes (female genotype) or one X and one Y chromosome (male genotype)  
      • A chromosome pair contains one chromosome inherited from each parent.
  • Germ cells (sperm cells/ova) only contain 23 SINGLE chromosomes (no chromosome pairs!)
      • In other words, they are a haploid chromosome set with only one copy of each chromosome.   (NB every other cell in the body has a diploid set of chromosomes)
      • When a couple have a baby, one part of the pair of each of the 23 chromosomes comes from each parent. 
      • This enables diversity as population generations progress.
  • Expressivity is the extent of expression of a given genotype at the phenotypic level.  In other words, to what extent does the abnormal gene express and manifests itself as a disease?  Patients with Marfan syndrome present with highly variable manifestations of the disease.  Some have mild Marfan’s (arachnodactyly) to a whole variety of presentations including the severe life-threatening (aortic aneurysm) form. 

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Bradford VTS was created by Dr. Ramesh Mehay, a Programme Director for Bradford GP Training Scheme back in 2001. Over the years, it has seen many permutations.  At the time, there were very few resources for GP trainees and their trainers so Bradford decided to create one FOR EVERYONE. 

So, we see Bradford VTS as  the INDEPENDENT vocational training scheme website providing a wealth of free medical resources for GP trainees, their trainers and TPDs everywhere and anywhere.  We also welcome other health professionals – as we know the site is used by both those qualified and in training – such as Associate Physicians, ANPs, Medical & Nursing Students. 

Our fundamental belief is to openly and freely share knowledge to help learn and develop with each other.  Feel free to use the information – as long as it is not for a commercial purpose.   

We have a wealth of downloadable resources and we also welcome copyright-free educational material from all our users to help build our rich resource (send to

Our sections on (medical) COMMUNICATION SKILLS and (medical) TEACHING & LEARNING are perhaps the best and most comprehensive on the world wide web (see white-on-black menu header section on the homepage).