Lymphoedema is the accumulation of subcutaneous fluid caused by dysfunction of the lymphatic drainage system, which most commonly presents as swelling (oedema). In some cases, swelling of the legs or arms of children will have an identifiable genetic cause.

Premature ovarian insufficiency is a highly heterogeneous condition that can be associated with autoimmune diseases, cytogenetic anomalies and pathogenic variants in more than 75 genes.

Some neonates and older infants may present with dysmorphic features in combination with one or more major congenital malformations. In such cases, investigation for a genetic condition may be valuable.

A significant proportion of babies or children admitted to neonatal or paediatric intensive care units (NICU or PICU) will have an underlying genetic condition that is responsible for their clinical presentation.

Girls with Turner syndrome have one normal X chromosome, rather than the usual two. They can present pre- or postnatally with a range of clinical features.

Patau syndrome (trisomy 13) is a genetic condition resulting from the presence of three (rather than the usual two) copies of chromosome 13. It has varied clinical features, commonly including intrauterine growth retardation, microcephaly, cardiac defects, small or absent close-set eyes and extra fingers. It is a severe condition that often results in stillbirth or death in infancy.

Edwards syndrome (trisomy 18) is a severe, multi-system genetic condition resulting from the presence of three (rather than the usual two) copies of chromosome 18. It is often identified during prenatal screening, but may present postnatally.

Down syndrome (trisomy 21) is a genetic condition caused by the presence of three (rather than the usual two) copies of chromosome 21. It is often identified during prenatal screening, but may present at birth or in early childhood.

Most cases of short stature are due to inadequate food intake and/or acquired disease, but a minority will have a genetic cause.

Hypotonia, which presents in infants as floppiness, can have an acquired, central or neuromuscular cause. Genomic testing is an important part of investigating a hypotonic infant because almost 50% will have a genetic condition.