The genetic alteration behind many diseases that goes unnoticed: "I've never felt ill"

BarcelonaAt 25, Germán's first gray hair appeared, and by 30, his hair was already completely white, but he didn't think anything of it, attributing it to stress. Since his father died of pulmonary fibrosis and he bears a strong resemblance to him, he's always taken care of himself, exercised regularly, and has never "felt ill." Even so, when he was 43, he developed bronchitis that didn't completely clear up. He saw various specialists and was finally hospitalized at Vall d'Hebron, where he underwent numerous tests.

He was diagnosed with a genetic disorder that caused the disease in his lungs, like his father's, but which was also responsible for the premature graying of his hair. These are called telomeropathies, and now Germán is one of the 30 patients receiving treatment and support in a pioneering unit that the Catalan hospital has set up to diagnose them, as they often go unnoticed. This is the first Adult Telomere Biology Alteration Unit in Spain.

"Like the plastic that protects shoelaces and prevents them from unraveling, telomeres protect the ends of chromosomes, and if they are altered, DNA is damaged and diseases appear," explained hematologist Julia Genetico Hematológico from Vall d'Hebron at a press conference this Thursday. Thus, people with this alteration have shorter telomeres, which are the regions of DNA that protect the ends of chromosomes.

From gray hair to blood cancer

Germán is the youngest of five siblings, and all of them have been treated in this pioneering unit because they all have the genetic disorder. However, only he and his older brother have diseases caused by the mutation, since being a carrier of a mutation in the telomere biology genes does not necessarily mean having to suffer from a disease. However, having shorter telomeres can lead to diseases associated with aging, such as cancers that affect the blood, bone marrow, or lymph nodes; pulmonary fibrosis; or liver disease.

Telomeropathy is more commonly detected in children when a serious illness, such as blood cancer, develops, or when they have diseases that are more common in older age. However, it is underdiagnosed in adults, which is why the hospital launched the unit in 2024. Patients may present milder symptoms, such as premature graying of hair, oral lesions, skin conditions, recurrent infections due to low immune defenses, or anemia. In fact, one of the unit's goals is also to determine the incidence of these genetic disorders, as it is currently unknown due to underdiagnosis.

Smoking and sunbathing shorten telomeres.

Advances in recent years in the study of genetics have made it possible to link a series of diseases to telomere alterations, changing the approach to these pathologies. "Previously, the disease was treated and no one knew why it occurred; now we're trying to answer why it happens," explained the unit's genetic counselor, Sara Torres-Esquius.

The unit employs various specialists, such as geneticists, hematologists, hepatologists, oncologists, and psychologists, to address the range of diseases that this genetic alteration can cause. However, the origin of the problem, the mutation, is not important, since telomeres cannot lengthen, according to the doctors.

There are some lifestyle factors that can shorten telomeres more quickly over the years, such as excessive sunbathing or smoking, but this is not the case for the people treated at the Vall d'Hebron unit, as they suffer from these conditions due to a congenital alteration.