Though these findings are a large step in determining the underlying cause of FHS and widely accepted, others would claim molecular diagnosis is not always successful and the mutation is not a mandatory feature for the diagnosis of FHS. Diagnosis
Until recently, doctors have diagnosed patients with FHS based on clinical observations and how well they fit the disease description, usually occurring in early childhood. Molecular genetic testing is also used now to test for genetic mutations. By performing a sequence analysis test of select exons, mutations can be detected in exon 34 of the SRCAP gene. This mutation has been observed in 19 patients to date. In most cases, if the patient shows classic facial features of FHS, the molecular testing will show a mutation on the SRCAP gene. Differential diagnosis
FHS shares some common features with Rubinstein–Taybi (due to overlapping effects of mutations on SRCAP), however cranial and hand anomalies are distinctive: broad thumbs, narrow palate, and microcephaly are absent in Floating-Harbor Syndrome. One child in the UK has a diagnosis of microcephaly alongside Floating–Harbor syndrome. Management
There are no cures for FHS. Close monitoring of growth in the first few years is essential, as well as annual general health screening and tests listed below. An FHS diagnosis will affect the individual and those there to support them.Managing symptoms and features of FHS involves maintaining a close watch on the patients physical as well as mental health.
Floating–Harbor syndrome, also known as Pelletier–Leisti syndrome, is a rare disease with fewer than 50 cases described in the literature. It is usually diagnosed in early childhood and is characterized by the triad of proportionate short stature with delayed bone age, characteristic facial appearance, and delayed speech development. Although its cause is unknown, it is thought to result from genetic mutation, and diagnosis is established by the presence of a heterozygous SRCAP mutation in those with clinical findings of FHS. Signs and symptoms
Below are the common clinical features of those diagnosed with Floating–Harbor syndrome. Patients will show varying degrees of some or all FHS symptoms. Facial abnormalities  are the most defining aspects of those diagnosed with this disease. Cardinal facial features
Triangular face
Deep-set eyes
Short philtrum
Wide mouth with a thin vermilion border of the upper lip
Long nose with a narrow bridge and broad, bulbous base
Low-set ears

Voice quality and language
Dysarthria and verbal dyspraxia with phoneme imprecision
Hypernasality
High-pitched voices
Severe receptive and expressive language impairment across all domains of function

Bodily features
Significant delay in bone age (-2 SD or greater) with normalization between 6–12 years old
Skeletal anomalies: brachydactyly, broad fingertips or clubbing, clinodactyly, short thumbs, prominent joints, clavicle abnormalities
Short adult stature: for females, maximum height was at the 20th percentile; for males, the maximum height was at the 25th percentile, though male height varied more widelyThe differential diagnosis of broad thumbs includes Rubinstein-taybi syndrome, where they are a cardinal feature.