CSNK1D rs28532483: Circadian Timing and Migraine
The genetic variant rs28532483 is an extremely rare missense alteration in the CSNK1D gene, commonly referred to in biomedical literature as the T44A mutation. It alters the structure of casein kinase 1 delta, an enzyme essential for calibrating the speed of the human body's molecular circadian clock. Inheriting this variant has been linked in familial pedigree studies to familial advanced sleep phase syndrome and an increased susceptibility to migraine headaches.
What each genotype means
Typical circadian rhythm
This genotype represents the common, wild-type sequence for the CSNK1D gene. It is associated with standard circadian rhythm regulation and does not carry the T44A mutation linked to familial advanced sleep phase syndrome.
This is the most common genotype found in the general population across all ancestries.
Potential circadian rhythm variation
This genotype includes one copy of the T44A missense mutation, which has been linked to familial advanced sleep phase syndrome and migraine in some research studies. Because this condition follows an autosomal-dominant pattern, individuals with this variant may experience significantly advanced sleep onset and offset times. Please discuss any concerns regarding sleep patterns or health history with a qualified clinician.
This specific genotype is extremely rare, with the T44A variant occurring at a frequency of less than 0.01% in gnomAD population databases.
Rare circadian rhythm variant
This genotype indicates the presence of two copies of the T44A mutation. Research suggests this mutation accelerates the internal biological clock, potentially leading to familial advanced sleep phase syndrome and an increased susceptibility to migraine. As this is a rare genetic finding, you should consult with a medical professional or genetic counselor to discuss the clinical relevance of this result for your health.
This homozygous genotype is exceptionally rare and is not typically observed in standard population frequency datasets.
What is rs28532483 and where is it located?
The variant designated rs28532483 is a single nucleotide polymorphism positioned within the CSNK1D gene on human chromosome 17. At the molecular level, this mutation causes a single nucleotide exchange that alters the reading frame of the messenger RNA, leading to the substitution of the amino acid threonine with alanine at position 44 of the polypeptide chain (p.Thr44Ala, often abbreviated as T44A). Because this substitution changes the biochemical properties of a core region of the protein, it directly affects how the resulting enzyme operates. In the standardized clinical genetics literature, this variant is cataloged in databases such as ClinVar and dbSNP under entries for monogenic circadian traits. The majority of the human population carries two copies of the wild-type, reference allele, while the altered non-reference allele is observed with extraordinary rarity in the broader population.
The biological function of CSNK1D
The CSNK1D gene provides the instructions to manufacture casein kinase 1 delta (CK1δ), a serine/threonine protein kinase with fundamental regulatory responsibilities in cellular biology. One of its most vital roles is serving as a molecular timekeeper for the central circadian pacemaker. CK1δ directly phosphorylates key circadian repressor proteins, notably members of the PERIOD family such as PER1 and PER2. Phosphorylation controls the stability, nuclear accumulation, and subsequent proteasomal breakdown of these clock components. By orchestrating this continuous molecular cycle of synthesis and degradation, CK1δ establishes the approximate 24-hour cycle of human physiology, dictating daily fluctuations in hormone secretion, core body temperature, alertness, and sleep drive.
What the research says about sleep phase and migraine
Genetic linkage studies in multi-generational families originally identified the T44A substitution in kindreds demonstrating familial advanced sleep phase syndrome type 2 (FASPS2). Affected individuals frequently fall asleep around 6:00 to 8:00 PM and awaken naturally between 2:00 and 4:00 AM, driven by an accelerated internal circadian period length. Subsequent functional and biochemical assays revealed that the T44A mutation slightly diminishes CK1δ kinase activity, disrupting the normal phosphorylation timing of PER2. Interestingly, researchers observed that family members carrying this mutation experienced a significantly elevated prevalence of migraine with aura alongside early-phase sleep patterns. Animal models engineered with the corresponding mutation replicated both shortened circadian rhythm periods and lowered thresholds for cortical spreading depression, the neurophysiological correlate of migraine aura. However, because these findings stem largely from isolated family pedigrees and targeted molecular studies, scientific evidence regarding general population penetrance remains limited.
How common is rs28532483 across populations?
Variant rs28532483 is classified as an extremely rare variant in broad human reference datasets. Population genomics aggregators, including the Genome Aggregation Database (gnomAD), record a global minor allele frequency (MAF) of well under 0.01%. Outside of specifically ascertained families affected by inherited familial advanced sleep phase syndrome, the variant is almost completely absent across all continental genetic ancestries, including European, African, East Asian, South Asian, and Latino populations. Large-scale population biobanks, such as the UK Biobank, that evaluate rare missense variants have noted that classic monogenic circadian mutations rarely appear in general cohorts, underscoring that rs28532483 does not account for typical variation in ordinary 'morning lark' or 'night owl' chronotypes observed among the general public.
What you can and cannot do with this information
Discovering an association with rs28532483 provides educational insight into the fundamental genetics of circadian biology, but it should not be treated as a definitive medical diagnosis. Because the variant's penetrance and expressivity have primarily been studied in distinct family lines, possessing an alternative genotype in consumer genetic datasets should always be verified by an accredited clinical laboratory before drawing conclusions. Genetic data cannot predict whether an individual will develop clinical migraines or how severely their sleep architecture will shift. Individuals with chronic migraine or debilitating circadian rhythm disruption must not change lifestyle routines or medications based solely on genotype data. If you have questions regarding sleep disruption or severe headaches, consult a qualified physician, sleep specialist, or genetic counselor to discuss clinical evaluation and evidence-based management.
How common is this variant?
The rs28532483 variant is extraordinarily rare globally, exhibiting a minor allele frequency of less than 0.01% in gnomAD. It is virtually undetected across general global populations and has primarily been documented in specific familial kindreds.
Frequently asked questions
Does carrying the rs28532483 variant mean I will definitely get migraines?
No. While research within specific carrier families found an increased prevalence of migraine with aura, carrying the variant is not a guarantee of developing symptoms. Migraine is a complex neurological disorder influenced by numerous polygenic risk factors, environment, hormonal fluctuations, and lifestyle.
Can rs28532483 explain why I naturally wake up early in the morning?
It is highly unlikely. Most normal variations in chronotype—such as being a 'morning lark'—are influenced by hundreds of common genetic variants acting together rather than a single rare mutation. Because rs28532483 is exceptionally rare in the general public, it is almost exclusively seen in families with extreme familial advanced sleep phase syndrome.
How does the CSNK1D gene change human sleep timing?
CSNK1D produces casein kinase 1 delta, an enzyme that regulates the breakdown and timing of internal clock proteins like PER2. When the T44A mutation alters the enzyme's activity, the molecular cycle completes faster than 24 hours, causing the body's internal clock to advance sleep and waking times substantially earlier in the day.
Should I confirm my raw genetic data if it reports an rs28532483 variant?
Yes. Direct-to-consumer DNA tests occasionally produce false-positive calls when genotyping extremely rare single nucleotide variants. If a rare variant like rs28532483 appears in your raw file, a certified medical genetics laboratory must perform clinical confirmatory testing before drawing medical conclusions.
Sources & further reading
Educational information only, last refreshed 9/6/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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This missense mutation (Thr44Ala) in the CSNK1D gene is a known cause of familial advanced sleep phase syndrome (FASPS).
A rare missense variant (p.His205Arg) in CSNK1D causing familial advanced sleep phase syndrome type 2.
Missense variant (Thr44Ala) in CSNK1D; pathogenic for Familial Advanced Sleep Phase Syndrome 2 (FASPS2).
Exonic variant in CSNK1D; while some variants are linked to advanced sleep-wake phase syndrome, population-wide penetrance is often low.
This variant in CSNK1D is linked to familial advanced sleep phase syndrome, influencing circadian period length.
This variant is linked to advanced sleep phase syndrome, affecting the regulation of the circadian clock.