Is this a joke? And doesn’t it an awkward one?

Is this a joke? And doesn’t it an awkward one?

The passage below is from Jellyfish age backwards by Nicklas Brendborg.

Researchers are still doing twin studies, but they have also

begun employing new study designs to untangle genes and

environment. For instance, Google-owned Calico (California

Life Company), has conducted a study in collaboration with

Ancestry.com, which hosts more than 100 million family

trees. These family trees include enormous amounts of data

on the lifespans of different families, which can, of course, be

analysed.

The result of the study confirmed the low heritability of

longevity. That is, while your genes are highly influential on

many traits, they don’t matter much to how long you live.

Actually, the Calico researchers discovered that genes might

be even less important than suggested by twin studies. They

found that married couples – who generally are not related

– have more similar lifespans than opposite-sex siblings. And,

overall, there is a correlation between the lifespans of a given

family and those who marry into it. This might be of some

comfort if your mother-in-law has moved in and refuses to

give up the ghost.

The underlined sentence seems to mean that since blood relations don’t have much to do with longevity, you don’t have to worry about your mother-in-law’s refusing to die. Your mother-in-law’s longevity don’t tell you wife will live long.

(Am I right?)

But I have additional questions.

Is this a joke?

(Am I right?)

But is this joke a proper one to tell your acquaintances?

Thanks in advance.