Head Of Section: Andy Pearce

Telephone 0131 537 2998
The Postnatal Cytogenetics Section performs constitutional chromosome analysis and microarray analysis on venous blood samples.

Referral Indications; Specimen requirements; Rapid trisomy analysis; Male Factor Infertility; Success Rates


Referral Indications

Microarray Studies   see page

  • Unexplained learning difficulties/developmental delay 
  • Dysmorphology/multiple congenital abnormalities suggestive of a chromosome abnormality
  • Microdeletion or duplication syndromes

G-Banded Chromosome (karyotyping) Studies

  • Ambiguous genitalia or indeterminate gender
  • Delayed puberty or inappropriate secondary sexual development
  • Short stature, amenorrhoea in females
  • Oligospermia or azoospermia in males
  • Family history of a known chromosome abnormality other than simple aneuploidy due to non-disjunction
  • Suspected family history of chromosome abnormality where the karyotype of the affected individual is not known
  • Sperm and egg donors


Other

  • Chromosome breakage studies (please send to Aberdeen)


Specimen Requirements

Note: Referring clinicians are requested to comply with NHS Lothian policy on Mandatory Data Sets:  Failure to do so will result in delays in processing or rejection of the sample.

Volume of Whole Blood Required

Lithium Heparin tubes (plastic orange top)

and

EDTA tubes (plastic purple top)

Adult and Children

2mls

New Borns

1ml

Foetal Blood (cardiac or cord blood)

0.2 - 0.5ml

Referral forms can be downloaded.

Any special requirements (e.g. Molecular Cytogenetic (FISH), urgent result) must be discussed by telephone with either Head of Service (0131 537 2993) or Head of Section (0131 537 2998) before taking and sending the sample.

Arrange for immediate transport to the Laboratory.  If this is not available, blood specimens should be placed in a cool place or at 5°C in a refrigerator (DO NOT FREEZE).  It is advisable to telephone the Laboratory on 0131 537 2990 to alert the Laboratory as, occasionally, specimens are lost during transport.


Rapid Trisomy Analysis

Rapid QF-PCR trisomy screening can be offered in addition to the karyotyping service where there is a clear indication of Trisomy 21. Any other referrals for this service must be discussed with Clinical Genetics.


Male Factor Infertility Kit

Y chromosomal microdeletions are the second most common cause of male infertility after Klinefelter’s syndrome with deletion frequencies varying between 2 and 10% in azoospermic men, dependent on patient selection (Krausz et al., 2013).
Clinically relevant deletions have been identified in three regions of the Y chromosome, AZFa, AZFb and AZFc.
Testing of Y microdeletion by QF-PCR is available for patients with azoospermia (sperm concentrations < 2x10^6/ml).
Please note:  This test requires 2-5mL of peripheral blood in an EDTA tube.


Reporting Times and success rates

 

National Target

Non-urgent referrals Reporting times

95% within 28 days

Urgent referrals reporting times

95% within 10 days

 

Details of Limitations of Cytogenetic investigations are available.

Last Reviewed: 29/09/2017