Genetic Testing - The importance of Clinical Details
Clinical details are very important when providing genetic analysis. The more clinical information that is available (eg; details of ultrasound information, phenotypic features or family history) the better the service we can provide.

CYTOGENETICS
Cytogenetic analysis is performed according to the Professional Guidelines of the Associated of Clinical Cytogeneticists and the recommendations provided are dependent on the clinical indications given for each case.

Clinical details inform the investigation at all stages:

• Prior to analysis, clinical details may indicate, for example, that specialist procedures such as chromosome breakage or leukaemic studies are required, which must be referred to a specialist centre.
• During analysis they may indicate that extra cells should be screened to investigate the possibility of mosaicism, for example in a diagnosis of suspected Turner syndrome, or that particular chromosomes must be targeted for high-resolution study, for example chromosome 8 in suspected Langer-Giedion syndrome.
• When the analysis has been completed they may help to provide an accurate interpretation of the findings and in some instances prompt further investigations, for example FISH or molecular genetic studies.
  

When clinical details are not available a routine analysis will be performed and a conditional report issued.

MOLECULAR GENETICS

Clinical details can be extremely important for clinical interpretation of a molecular genetic test.

For example, the clinical comments accompanying a cystic fibrosis screening report will vary depending on whether the patient is a potential gamete donor or a person exhibiting a cystic fibrosis phenotype. Similarly, the interpretative comment accompanying Factor II and V studies may vary depending on whether the investigation is prompted by a history of recurrent miscarriage or the need to determine a thrombotic risk.

It may also be crucial, where a mutation has already been shown to be segregating in a family, to be provided with information concerning the mutation and a family pedigree to ensure the correct analysis is performed and reliable risk figures calculated.

Notes for Cytogenetics

As cytogenetic studies require living cells, please ensure that samples reach the laboratory quickly. If a delay before despatch is unavoidable, samples may be stored in a refrigerator (4°C) but they must NOT be frozen.

Information concerning packaging, transportation, and labelling of samples is provided on the inside cover of our TDL Genetics Request Form Pad.

On completion of analyses, fixed cell suspensions are stored for a minimum of three months and are available for additional follow-up studies (for example, FISH), if necessary.